Um, you have to use the iTunes store? Why does everyone always assume that as soon as one uses iTunes, music is also bought that way? I used iTunes for a long time without ever buying anything there.
You're right, I shouldn't assume that; however, I bet that the majority of the users of itunes use the store because the itunes store has the most buyers of any music store (that fact was true when I read it, but it may have changed, but if it did change, itunes would still be one of the leaders)
I like this unofficial solution.