I think all the info you need for that is in the help files. There are also tutorials there.
There's no need to bounce the tracks to a "Master Track", that's not how things are usually done.. When you want to, say, burn your project to a CD or convert it to a stereo MP3, you export it to a wav-file and then convert it to MP3 with the converter of your choice.

Thanx Kalle.. Much appreciated..

I understand the Burning and converting but it is the stage before that I am confused..
 
I have a backing track in audio and a couple of separate guitar tracks and I want to put them together so I can put them on an MP3
 
I'm reading about sends and buses and it seems very complicated

Yes, it's complicated. And the deeper you go the more complicated it gets.
 
But like they say, if it was easy everybody would be doing it!
 
I'd suggest kicking back with a beverage and watching some videos.
 
Granted, most of the stuff in Cakewalk's YouTube collection is intermediate-level, and mostly X3-related, but a great deal of that information is still relevant to SONAR 5. Try this one as a starting point. Here's one about sends and busses.
 
There are videos about many basic functions, and even though most are demonstrated on more recent versions of SONAR, the basic layout hasn't changed so much that you won't be able figure out what's what. A track is still a track and a bus is still a bus, and other terminology is mostly the same too.
 
 

Thanx for your time and help bitflipper, It is much appreciated and I will chill for a while and view the vids that you have given me....