I remember a thread not long ago, which made me wonder if there are any websites which have background music to download to practice playing to/with.
Well, come to find out my husband has a boatload of these. Just about every blues progression possible, as far as I can tell. My son is playing along to one right now. He was balking with practice, and I said, "Remember, Jared says playing along to music is practice, do you want to go play the blues?" his eyes lit up, and here we sit. He is rocking out. or bluesing out. Here is the link. You have to go where it says "backing."