I'm bored with my music. HELP!

Ok so I primarily listen to rap and hip-hop. ALL sorts. And I am terribly bored with everything on my iTunes. I need advice on new stuff to listen to!
Some of my favorite albums of all time are Kanye's first two (College Dropout and Late Registration), De La Sol's 3 Feet High and Rising, EPMD's Strictly Business, Jay-Z's Reasonable Doubt, and Nas's Illmatic. I also love individual songs from all sorts of artists: from the greats to the lesser-knowns. Tupac, Biggie, Ice Cube, Mos Def, Method Man, Lupe Fiasco, Wiz Khalifa, N.Y.C., Lil Wayne, Brand Nubian, Boogie Down Productions, etc., etc.
As you probably can see, I primarily listen to more mainstream rap, simply because I don't know of many underground artists. However, if you feel I missed some mainstream artist I would love to know! 
PLEASE HELP ME!!! (and thanks to all of those who do!)