Ok, so I've got the bug...!!!
 
I've bought a copy of sonar x1 and a ldc (mxl 990) microphone and an m audio m track, the aim at first is for me to record vocals against an acoustic guitar track, played by my friend, already laid down and recorded to a wav file on my pc.  My pc is a beast and can handle anything and I'd like to use sonar to refine my vocal performance and the acoustic wav file and produce it by possibly adding other things to make it sound great.  Who wouldn't?!
 
Whilst I'm still learning the basics of sonar, through the helpful tutorial videos, I'm looking to get into this properly and was wondering if some of you helpful chaps would give me a hand in explaining the following:
 
1: What do plugins and fx do?  Is this what i need to use on the software to do what i want as stated above?
 
2: With regard to adding more new sounds, drums etc, i'm looking at purchasing a MIDI keyboard? The way i understand is that with a MIDI keyboard i can create music upon a variety of instruments by hitting the note or selected sound I have assigned to that particular key - is this correct?
 
3: If my assumption above is correct (and i understand that MIDI is a piece of electronic information and not a sound), why are MIDI keyboards advertised as a usb bit of kit, when i have an interface that i can plug them straight into - whats the difference? I should be plugging them into my interface surely? (Being an Atari ST owner from back in the day - i certainly recognise those ports!)
 
Finally, whilst i realise i don't necessarily need a midi keyboard today! I'd really like to have a better understanding of why purchasing one would be beneficial to me in the long run.  I'm not a piano or keyboard player, but then again, i don't believe i need to be........do I?.....yet?
 
Thanks in advance.
 

1. Plug-ins are software added to the basic DAW (in this case SONAR X1) to extend it's features. Plug-ins fall into two categories effects and instruments. Effects could be used to refine and enhance a performance.
2. Yes
3. Recently, it has become popular for keyboards use a USB connection to the PC. Not only is this convenient, it lowers the cost of manufacture because the keyboard power is supplied via the USB cable. Some keyboard still have MIDI DIN connectors which require an additional piece of hardware to get the data into a PC and an external power supply. This hardware could be a cable style adapter, a dedicated MIDI interface or a combination Audio/MIDI interface. It does not matter which connection style is used, they all work just as well.
4. SONAR provides several ways to enter/edit MIDI data but to enter data in real-time (while playing back other tracks) requires an input device. This is the reason for the keyboard. One does not need to be proficient at keyboards to take advantage of entering data via a MIDI keyboard.

badhoon
Ok, so I've got the bug...!!!
 ........
Finally, whilst i realise i don't necessarily need a midi keyboard today! I'd really like to have a better understanding of why purchasing one would be beneficial to me in the long run.  I'm not a piano or keyboard player, but then again, i don't believe i need to be........do I?.....yet?

Steve has covered your questions pretty well, I think.
For myself, my MIDI controller is decidedly one of the most valuable assets in my little studio.
While it's true you can create MIDI tracks with the PRV or Step Sequencer, actually playing your virtual instruments with a keyboard allows you to control subtle nuances, much as you would with a guitar.
If you like the idea of performing your parts live, as opposed to programming, a keyboard controller is king.
I'm not a keyboard player either, but I'm getting better at it.

Right.
A MIDI keyboard will give you better control of the dynamics of the instruments. If the keyboard is touch/velocity sensitive (recommended), it will 'record' how loud you play. When entering data with your mouse, the notes will always be the same velocity/volume and will require lots of editing for that "real" instrument sound.
If your audio interface has MIDI ports, I recommend getting a keyboard with MIDI connections. That way you don't have to worry about whether the USB drivers for the keyboard will work well on your system.

Cheers Gents.
 
Reading my post back it obviously shows that I am but an apprentice...I appreciate your wise words in helping me getting my head around the basics!
 
Going back to my first point then, i really need to focus on the fx side of the plug ins first to help trim and 'track' the vocals of what i would like to do?   
 
Also with that in mind - could anyone give a brief explanation of what the synth rack is for? - is this just primarily for me to record my MIDI keyboard 'sounds' into to be used in the project?
 
By the way - i have a background of video editing which may explain the terms i use and the way i think in applying similar traits to using this type of software.  But I do appreciate your time in giving me the handy hints and tips i need to get started.
 
If you need a hand with video editing - just ask...!  

Plug-ins are not useful for tracking. Tracks are recorded dry into the DAW. Software effects are used after the track is recorded.
 
The synth rack is mostly an organizational tool. It displays all the softsynths used in a project. When a synth is inserted in the project, it is added to the synth rack.

Sorry - my bad with the terms i think - by tracking I talk as a general term and mean finely editing - i.e. adding an effect onto the pre-recorded track to make it sound different (as in polished,echoed etc) and also having the ability to remove the peaks and troughs and unwanted sound?

There are two ways to record mainly. Either like a live setup (like playing live in a band) and recording each musical instrument separately onto tracks in Sonar with the inputs and outputs of an audio/interface or musical instrument as in Audio Recording, or via recording with MIDI (say from a keyboard) just the note values and either playing like said before, or editing it all in Sonar afterwards.
 
On each track is a section for adding a FX effect in and out or by adding (say like echo and reverb) to a track (say vocal) with an Audition setting that can vary from a few seconds up to say 25 seconds after changing the vocal that was dry with the echo or reverb to hear what it will sound like before changing anything. Then you can have Sonar change it, and well if you do not like it afterwards you can "undo" in the Edit menu item or "redo" if you want to hear it all again, and edit the recording in Sonar. Afterwards either by adding (effects- FX) in the setting option for that in each track or changing so it will always be that way (audition and changing) then you save it all in the file and the song project will always be that way when you load it back up or export it out of Sonar into a Wave file or *.mp3 file or whatever file you export it as.
 
You can do as a live band kind of for each track if you have outboard equipment that adds echo or reverb or whatever to the track as you are recording it (and produce the audio type file of the input) or do dry and record it and change it then in Sonar by the other method for the track.
 
As for a keyboard you can also record that as an audio file with the line outputs of the synth or record the track as a midi track with the midi output or perhaps both ways with the USB connection, although I prefer the line outputs or midi connection and do not use USB, because USB can also be used with another program by the synth manufacturer perhaps to change sounds on each patch of the synth and store those back into the synth by using that other program and saving the sounds back to your synth.
 

You can add effects in the effects (FX) bin of any track.  You probably have several with your copy of X1.
You can insert an EQ in order to tame incipient muddiness or make a track brighter. Add reverb of varying degrees to the tracks to give the song a sense of space. Add a special effect like a vocoder to give your voice that robot feel. You can use a plug-in to correct intonation. You can add a compressor to a track so it is at near the same volume consistently.
But you can't remove clipping and/or distortion if the track recorded that.

You can Normalize a track so it is at the same volume consistently

 
Have to disagree with you on that one. Normalization will simply raise the entire level of the wav up to a user defined level, with reference to the level of the highest peak. It will not change the ratio of high levels to low levels.
Compression is what you need to restrict the dynamic range