Unfortunately, you have to pay for it; I guess I'll use it as last resort if I cant really scour the internet for backtrack of one song.
I entirely agree. As much as I take issue with various elements of the economy, somebody has put time and effort into creating those tracks. If they choose to release them for free, that's great but making backing tracks like that is a profession for some and need to earn money as a result. As a poacher-turned-gamekeeper there I can see where the OP is coming from but I can't agree with him. I used to pirate music (when I was a teenager) but I don't any more and instead make my own. I offer it for free because it's not my job and something I do in my spare time but if I was relying on it as a major source of income, you can bet your bottom dollar I'd be charging.WTF?
Of course you pay for it. That's the way the world works: If you want something of value you have to give something of value in return.
Cue discussion of the value of music, the pros and cons of playing for free etc.