Developing & practicing music improv style

It might take a while, but I could more than likely get you an insane amount of it. My Dad hosts jam session that encompasses blues/bluegrass/acoustic/jazz/hippy/whatever else you could imagine. I'll ask him if he has anything for you and let you know.

Nizzle?

Sounds like you need bass sounds and drums for your jam session. A drum machine is a fine idea. Many of the inexpensive Casio and Yamaha fun keyboards have built in drum machines and even sequences in various styles. Some are interesting enough to play along with. When I teach my students how to improve lead lines, I use a Yamaha Clavinova. The student will play on their own keyboard or guitar. On the Clavinova I dial up the appropriate drum beat and "kick bass"--split the keyboard so the lower notes are a bass patch. My left hand plays bass lines and my right hand plays chords or leads. Learning how to play bass with your LH is a very useful skill to master. You can create a virtual pseudo "band" with bass, chords and drums. Other options: 1. Make you own sequences--use garage band or any software you can find. Or, you could use a Techno beat record to jam along with. 2. There are commercial play along CD's. Most sound cheesy to me. In fact, I cannot even think of one to recommend, although, I'm sure there's got to be good ones out there. My hardcore jazz musician friends who play horns like the Jamie Aebersold series--do they have fusion play alongs? 3. You could be old school and just play with whatever instruments you've got on hand. Learning to play without a drummer is great for your rhythm. It can be fun. In fact, sometimes I prefer it. Bass on the other hand, is really hard to do without.

Sounds like a great idea. See, the commercial play alongs have to pay royalties. Anything really interesting will probably not be "wasted" on an educational CD. So making your own will give you a better result.

Do you have any Aebersold tracks? I have a bunch of them in MP3. Most tend to be in the "jazz standards" category, so maybe not your thing if you're into fusion or more modern improvisational styles. Look into software like Band in a Box that will let you set chord changes, tempo and playing style. BiaB is pretty simple and easy to use but again probably works best for more traditional music styles. If you have more time on your hands, you can set up backing tracks or build up loops in realtime with Abelton Live. Check out some Youtube vids of people using Live to see what I mean.

I have to agree that the vast majority of improv/backing track cds sound cheesy as hell.

I'd just take a few songs you like and use some guitar pro 5 software to manipulate it. Just go looking for the files. The backing tracks aren't too great in sound, but they're fun. Honestly thats better for one on one practice though :/