"Gin 'n' Juice" - Snoop Dogg (I can't believe it wasn't already listed)
"Smoke Two Joints" - The Toyes version (the original) is the best, but Sublime's version kicks as well.
"Because I got High" - Afroman
The stoner doom metal band High on Fire is a good band, if you like metal.
"Pass me the green" - Master P
"Fun with Drugs" Velvet Acid Christ (filled with samples from Fear and Loathing in Las Vegas)
"Hash Pipe" - weezer
"Legalize Marijuana" - Ziggy Marley
"Marijuana"/"Moist Vagina" - Nirvana. The lyrics have nothing to do with marijuana, it's kind of random, but the chorus shouts "Marijuana..."