Cephalic Carnage has a few songs about weed. Actually, I think most of them are.
But that's death metal stuff, so I dunno if it's really what you'd want.

Fantômas have a song called 4/20/05. Actually, they have an album out and each track is a different day of April, so it's not actually about weed...

sorry, this probably wasn't too helpful.
eight Reviewed by eight on . Marijuana Mix I'm co hosting a party this weekend to celebrate 4-20 and I was put in charge of music, does anybody know of any songs about marijuana? I already have a few; a couple Bob Marley Songs and some Grateful Dead. Rating: 5