46 & 2 - Tool.
Love Buzz - Nirvana
Lemon Song - Zeppelin
What everybody else said.
If you’ve only been playing bass for a couple of months, a lot of these suggestions are going to be way too hard. Any of the Primus stuff, for instance.
You are aware this is a Stevie Wonder song, aren’t you?
Get the Police album Zenyatta Mondatta and learn the whole thing.
Green Day has a lot of good ones, I think. “Longview” is fun for me.
As I read down the list, I see that all my favorites have been mentioned:
Jaco
Victor Wooten
Sting
Maynard
Les
and anything from
Yes
James Brown
Stevie Wonder
Dream Theater
seems most of the bases have been covered. I envy someone looking for some good bass riffs and hearing the above mentioned for the first time.
I’m a beginning bassist, and I think the first bassline I taught myself from listening to the song was Jack Casady’s bassline in Jefferson Airplane’s “It’s No Secret.” Simple yet beautiful.
I also like Paul Jackson’s bass work on Herbie Hancock’s album Thrust. I don’t think I was really able to play a lot of it, but it was inspiration that I was after anyway. Gotta get that proper funky attitude.
Good suggestions by everyone!
I’ve been playing bass since 1969. The best advice I can come up with is to play along with music you know and love. You’ll already be familiar with it, and learning to play it won’t be as difficult as for songs you don’t know yet. Make a mix tape or CD of all songs you like, and play them until you know them, and keep doing it until you get to progressively more sophisticated songs and can handle those as well.
I gotta say, it feels really cool to be able to play along with Paul McCartney on songs like “Come Together” or Chuck Rainey or Walter Becker on Steely Dan songs. The first time you get done and say to yourself "Holy crap, I just played “Deacon Blues!” (without making any mistakes) is almost better than sex.
Since I grew up in the late '60s and early '70s, sometimes I just put on a Time-Life compilation CD and play all the songs I know. I was pleasantly surprised to find I could keep up with the studio guys on stuff like The Fifth Dimension’s “Wedding Bell Blues” and Barbra Streisand’s “Stoney End”, songs you’ll never hear bar bands cover. I think the point I’m trying to make is that songs that are etched into your consciousness from constant hearing will be easier for you to learn to play because you know what’s coming up next.
I’d wait to figure out Jaco until you’re significantly more experienced.
Mama let that boy play some rock and roll, jazz is much too crazy, he can play it when he’s old, he’s too young for the blues, he’s still inside his first pair of shoes
- Jerry Doucette
A couple of months and you’re playing that Holy crap you must be talented. 
I’m a guitar player, but when I feel like playing bass I usually go for One of These Days (Pink Floyd), You need some FX (delay, fuzz, tremelo) but it’s a hoot to play.
And what everyone else says (Peaches/Ace of Spades/Money) plus the Beatles Rain (and let’s not start another discussion on this please).
Well. Duh! I love Stevie Wonder, but as far as covers go, wouldn’t you say that this is one of the most kick-ass? Honestly, I think I like it better than the original. And that I find very unusual.