There's a song that was used inan episode, perhaps in the second season. I've heard the song before, but now I can't remember the lyrics or the artist or anything. I wondered if anyone knew of a resource of sorts that listed all the songs that were used in a given episode.

That would be a great resource! I don't know why the producers don't provide one. There's a lot of great and obscure music on that show. :)

There was a 'Malcolm In The Middle' soundtrack album released in the UK a few years ago. I assume it's also available in the States. Since it was relased some time ago the songs on it are mainly from the 1st and 2nd seasons.
The track-listing is as follows:

1. They Might Be Giants - Boss Of Me
2. Stroke 9 - Washin' & Wonderin'
3. The Getaway People - Good Life
4. Baha Men - You All Dat
5. Eagle-Eye Cherry - Been Here Once Before
6. Barenaked Ladies - Falling For The First Time
7. The Push Stars - Drunk Is Better Than Dead
8. Citizen King - Bizarro
9. Travis - We Are Monkeys
10. Screamin' Cheetah Wheelies - Right Place, Wrong Time
11. Hanson - Smile
12. OPM - Heaven Is A Halfpipe
13. Flak - Tune In (Round Window)
14. Gordon - Don't Push It, Don't Force It
15. Rednex - Cotton Eye Joe
16. They Might Be Giants - Older
17. The Dust Brothers - I Just Don't Care

I have that soundtrack. Good songs on there. Actually the only reason I got the CD originally is because there is a Hanson song on there, but later I started to like the other songs and really like the show.

Frankie is a big Hanson fan, so I'm pretty sure he got that song on the album! :)