Good tips at http://www.guitarplayer.com/miscellaneous/1139/-seven-steps-to-amp-sim-goodness/23054
 
I use a DI box instead of relying on INST inputs, peak input at -10 and T-RackS White Channel up front for light compression and LP in the 10-12K range.  This works well with AmpliTube, Guitar Rig, GTR, Ampire, etc.  I'm sure it works great with TH2/3 too, but I can't get past the GUI.  Most of the time I use AmpliTube or the DI out of my Laney IRT Studio with cab emulation off.  I use one of the above with the amp section bypassed for cab/mic processing.
 
 
 

Westside Steve Simmons
Thanks for the info. I guess the convenience of switching sounds in a software plug makes a lot of sense. Do any of the plugs come with a plethora of presets and are any suitable for an acoustic guutar input as well?
WSS

POD HD is the most viable cheap option on the used market in my experience.  The presets are garbage, so you need to know how to set things up.  However, it does have a computer GUI if you connect via usb which makes programming sounds easy.
 
You can remove the amp sims and use an acoustic guitar, though recording guitar via a pickup is quite frankly a disaster in and of itself.  Guitar pickups just don't sound great.  
 
I strongly prefer playing guitar through hardware into an interface.  
 
Guitar players (myself included) tend to prefer switching between sounds with ones feet while they play.  Doing it in "post" from a plugin is terrible on so many levels.  
 
Are you looking for a solution for yourself or other guitar players (clients)?   If you are the guitar player what is your experience level?
 
Amp with Mic is the real way to do it, but that is not practical for a lot of people.  The really good products like the Kemper, AxeFX, Helix are not exactly cheap, and I'm implying from your initial post that you likely are not in the professional guitarist realm that these tools are really aimed at.  

I used to have POD, Digitech 1101, Vox Tonelab and Axe FX2 and still have and use two real tube amps. These days most of my tunes end up with guitar sounds from Amplitube 4 (Jet City is my favourite) and TH3 (Randalls). The list of factory presets in TH3 is excellent, also you can load third party cabinet IRs, you cannot do that in Amplitube. If you want to check the least expensive option try KAZROG amps (c. $8 each), the emulation of Friedmann is absolutely stunning.
 
Perhaps I would hold any serious investment before Craig Andertons new FX Chains come out.

Line 6 "Helix Native" (VST, AAS) just came out last week.  There is a free 15 day trial.  Check it out. 
 
http://line6.com/software/index.html?hardware=All&name=Helix%20Native&submit_form=set
 
Same sounds and engine as the Helix hardware. Some great stuff in there, except that it is a little light on cleaner sounds. Still, I bought it and am happy with it.  I can use the other stuff that comes with SONAR Platinum to get a good jazz or acoustic sound.
 
I like the Line 6 stuff for hardware and software.  The PODPro line works good for live and re-amping.  I have POD Farm 2.5 and Guitar Rig and use both with good results.  Sometimes I even run them in serial in the FX bin.  You can probably buy a used POD of some sort pretty cheap these days.  In fact, I have an old PODPro and a PODPro-HD (both with pedal-boards) I'll sell you real cheap, but shipping from Hawaii might be a bit spendy.  You can PM me if you are interested.
 
As far as the recording chain goes, I record through a preamp which sends a clean signal to SONAR and another to my Line 6 hardware which then feeds a little Fender tube amp for monitoring.  That way I can play/record with the inspiration of the processed sound (no latency) and yet record a clean signal that can be tweaked later with a plug-in or sent back out to the hardware for re-amping.

Slugbaby
Amplitube excels at simulating specific amps.  If you want that '65 Fender Twin or Marshall JCM800, that's what you get. It's very straightforward and simple.  They're licensed to Fender, Orange, Ampeg, and others, so they have to be great recreations.

As a present or past owner of several of the modelled amps, including two out of the Orange pack and one out of the Fender I'm afraid I don't entirely agree with that.

I agree that the Fender amp sounds that come in Amplitube are not very good but I own both of the Fender Collections and own most of those amps and I can tell you that while not the real thing they are very close. The Marshalls, of which I own 3 of those amps, in Amp4 are a vast improvement.
I really like the capability in Amp4 to change multiple speakers IN the cabs!!!! A 4X12 loaded with JBLs or EVs!! Holy crap!
Never been much of an Orange fan or the Boogie for that matter. Thought about picking up the Jet City.
Anyway, I think everyone has given good solid info here! Now, go make some racket.

Afrodrum
IPerhaps I would hold any serious investment before Craig Andertons new FX Chains come out.

Well thanks for the vote of confidence  but these aren't designed to be like AmpliTube or Guitar Rig, they're "hey, I just wanna play and get a good sound fast that I don't have to change on mixdown" modules. They're all I've used on my last two projects.
 
FWIW there was a solo I did with a "commercial" amp sim and I really liked, but one of the FX Chains actually gave better articulation. I think it's because of the output notch filtering taking away artifacts. 
 
There's still much to learn about what makes for a really satisfying amp sim experience...but that's what makes it fun 

Some great posts here,i was wondering if you all had any tips for getting a better sound when using something like Amplitube.
i have just read somewhere that adding a De-esser before the amp sim is a good step,anything else i can try ?
i have the audiobox usb audio interface, are there correct steps for the levels on my input on the audio device and then inside the actual amp sim for a better sound ?
 
Dan 

I have used the de-esser with great result but just placing a good graphic or parametric eq after the cab does wonders. A good starting point is leave everything flat and roll off everything below 100 Hz. Then roll off everything above 5 Khz. Then fine tune the roll off areas to smooth the response. This proves to be a more musical approach and more flexible.

tlw

Slugbaby
Amplitube excels at simulating specific amps.  If you want that '65 Fender Twin or Marshall JCM800, that's what you get. It's very straightforward and simple.  They're licensed to Fender, Orange, Ampeg, and others, so they have to be great recreations.

As a present or past owner of several of the modelled amps, including two out of the Orange pack and one out of the Fender I'm afraid I don't entirely agree with that.

That's entirely fair.
When I had my Fender Twin, it was so damned loud that I could almost never push it.  With the sim, i can get the sounds I THOUGHT I was getting at a usable volume.  Same with the JCM800, but maybe my ears just aren't catching the deficiencies.