That depends....what styles of music do you know? Can you be more specific as to what you're looking for?

i can recommend you listen a bit to P.O.D. its a bit different.

I take it your looking for something guitar oriented? If so, you might try Al DiMeola.

http://en.wikipedia.org/wiki/Elegant_Gypsy

Or The Dixie Dregs

http://en.wikipedia.org/wiki/Steve_Morse#Dixie_Dregs

Or Django Reinhardt

http://en.wikipedia.org/wiki/Django_rienhardt

If you already like rock/blues and want an easy-over to experience other styles, check out The Derek Trucks Band. They play a mix of blues and world music. If you want an album I'd get Joyful Noise, Live at Georgia Theatre or Songlines.

Alternatively, go to archive dot org and check out the Live Music Archive. Lots of freely distributable taped shows (including the DTB). Pick a name you like, download and listen. Most of the stuff on there is kinda jam-bandy.

If you learn a fair bit of john frusciante's work with the red hot chili peppers its makes for an easier transition over to more pure funk as its still pretty rock based

Get a classical guitar and study ;)

Try Joe Bonamassa for blues, he's really guitar orientated.

You should listen to Steve Vai. Most of his music has a wierd feel, as far as his early work goes, but his more recent stuff is TOPS. Go to my profile and check out the album i reviewed.

it depends if you would rather expand onto a heavier genre, or softer. eg: metal, jazz.
either way, all genres are good for playing guitar. they all teach you something different.
i play mainly metal, but im also very much into blues (SRV, Jeff Healey), and classical (Mozart, Bach etc). So, having an interest in all these different directions moved me to expand my guitar playing techniques (with ofcourse i am still doing).
So, if your looking to experiment with other genres, then i can honestly recommend you try EVERYTHING. from death metal to classical.
As for artists, it depends on the genre of course...

Derek and The Dominoes, Eic Clapton, Cream, Blind Faith, The Allman Brothers, B.B. King, Bob Dylan, Led Zeppelin, Johnny Cash, Waylon Jennings, Elvis, The Doors, Steve Vai, Joe Satriani, Jimmie Vaughan, The Beatles, The Eagles, Creedence Clearwater Revival, Stevie Ray Vaughan etc