guitarbackingtrack com is a nice place to download backing track mp3's

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free.  I slammed it into my favorite list so fast the lights dimmed.

http://www.guitarbackingtrack.com/

I tried samba pa ti  first since Santana is one of my gods (he knows more notes than anyone else does, on the same guitar yeah)

the number 6 choice turned out to be em/Gmaj = jam free in the good olde E box heh. so I downloaded it.
that was one fast hour of letting that thing just loop in the media player thru the stereo while I jammed the egnator tweaker nice and pretty.
http://www.guitarbackingtrack.com/play/santana,_carlos/samba_pa_ti_(6).htm

I seriously rate this as about as much fun as anything else I have done at any price: jamming to an infinite selection of backing tracks at will.

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oh boy. I hit a section in the j's of just jam tracks. random jams. some are just named track xx.

I spent some fun time with this one. e min and simple, so you can do the iommi riffs, or you can chugga chugga a more thrash feel,  play chromatic runs through the blues boxes for as meny notes as you can before choking or whatever.  Then you can have it repeat in your player/DAW so you can work the kinks out of the riffs and patterns.

http://www.guitarbackingtrack.com/play/jamtracks/heavy_metal_em.htm

grabbed a super slow Amin blues jam too. but that generic metal one sure is fun.
If that doesn't get you going, just listening to it, maybe you are flatlining heh. better check.

the thing I really like is it is set up to instantly download the mp3. no bullshit. bam done.  once you have it on your pc, then you can trim it to loop smoothly, or slice and dice it and make a song with your phrasing, add effects, eq up or down stuff..etc etc