You could go with Band In a Box.
www.pgmusic.com
Mostly geared to theory, jazz and such, it now comes with real drum samples. It's been around for 15 years and is a great tool for learning. You can loop sections of songs, slow down the tempo, create your own songs. Very powerful program and easy to learn. I highly recommend it to anyone who wants to learn jazz.
You can go online and search midi files of songs already created by folks. The program may come with a hundred or so in diff genres, but, I grabbed another 500+ online for free. Basically I got most of Realbook 1 & 2.
I'm sure there are tons of Rock songs as well out there.
