Mark Knopfler/Dire Straits: 181
Eric Clapton: 119
Paul Simon: 103
Bruce Springsteen: 93
Tom Petty: 74
Weird Al Yankovic: 65
Warren Zevon: 50
Melissa Etheridge: 46
Lyle Lovett: 43
My leader is Tom Waits at 366 songs, I just typed various artists’ names into the search pane and read the total at the bottom of the screen.
Classical music tends to be overrepresented since for one thing, movements of works are counted as “songs”, but the song leaders for me (not in precise order) are:
Bach
Vivaldi
Tom Petty
The Who
Genesis
Led Zeppelin
NRBQ
Mozart
Blue Oyster Cult
Haydn
The Dickies
Beethoven
Is it wrong that some people’s Top 3 lists are making me want to do some behind the scenes burning deals? Well, I mean, in the eyes of people other than the RIAA, that is. 
removed
The Simpsons 133 (from their various soundtrack albums)
Vince Guaraldi Trio 36
Celine Dion 29 (this is my mother’s, not mine)
Well, I don’t “iTunes” but in my mp3 player, I think Mozart wins…
Capercaillie - 122
Springsteen - 117
Jefferson Airplane - 80
Jimmy Buffett - 73
Sarah McLaughlin - 65
Grateful Dead - 64
Barenaked Ladies wins, at about 160.
The White Stripes are second at about 80.
So that’s about 15-20 minutes elapsed? 
Mine:
Cocteau Twins 192
Stereolab 134
Amon Tobin 116
Husker Du 106
Aphex Twin 104
Top 10, by number of songs:
- Oingo Boingo (471 - a bunch ripped from live bootlegs and the like)
- Alice Cooper (260)
- The Who (223)
- Ramones (199)
- Puffy Ami Yumi (196)
- Polysics (145)
- ‘Weird Al’ Yankovic (128)
- (tie) the brilliant green (113)
- (tie) Blur (113)
- (tie) Shonen Knife (99)
- (tie) Morning Musume (99)
Eels - 240
Wilco - 120
They Might Be Giants - 96
Barenaked Ladies - 91
Gogol Bordello - 77
Let’s see… I have just over 15,000 songs in my non-iTunes library. Using MediaMonkey to parse the library statistics:
314 - Chicago
207 - ‘Weird Al’ Yankovic
201 - John Lee Hooker
168 - Ray Charles
159 - Johnny Cash
128 - Big Joe Turner
123 - The Yardbirds
119 - Billy Joel
I’m reasonably sure the top 3 are correct. Four and Five are total guesses (I’m at work and I’m sifting through my iPod.
- U2 - 437 songs
- John Williams - 304 songs
- Jon Brion - 180 songs
- Hans Zimmer - 105 (there are more I’m pretty sure)
- Collective Soul - 61 songs
My problem is that I have piles of classical stuff by the usual suspects but they are all played by different orchestras, musicians, etc and I can’t really be bothered to sift through it all. I doubt i crack the top 4 though. I also have about half of my CD collection that I haven’t imported yet. I suspect Red Hot Chili Peppers, REM, Madonna (what of it), and a few others that are slipping my mind would all fall somewhere in between Hans Zimmer and Jon Brion.
I’m really amazed at some of these results - I thought I had a huge percentage of Prince’s albums, and here there is a guy with almost double my playlist. I thought I had almost every U2 album, and another guy has five times my playlist! I’ve definitely got some holes to plug.
Top composer: Mozart 730
Top artist: Ella Fitzgerald 547
GorillaMan, you nerd, I like your list. Stockhausen and Desprez.
And Roland. . . how does someone in Virginia become a big Daddies fan? The fact that they ended up known outside of 150 miles of Eugene, Oregon, is a trip, still.
My top 10 (I think):
Tom Waits–176 (wow)
Laurie Anderson/ REM–ties at 132
Kraftwerk–112 (not counting cover albums, which I casually collect)
Sonic Youth–110
David Bowie–104
Gary Numan–92
Pixies–90
Elliot Smith–79
Bauhaus–78
Nick Cave–77
Total: 2583 tracks.
Spike Jones with various bands: 121
Bill Cosby: 69
The Beatles: 63
Ella Fizgerald, solo and with others: 60
Mannheim Steamroller: 59
Bing Crosby, solo and with others: 48
The Moody Blues: 44
The Royal Guardsmen: 40
The Irish Rovers: 39
Canadian Brass, by themselves and with others: 39
The Mamas & The Papas: 37
Harry Connick, Jr.: 31
Mutt Poston with Clarence Jackson: 31
The Beatles.
6,026 tracks.
Depeche Mode 434
Erasure 350
Nine Inch Nails 261
Mesh 188
The Echoing Green 173
Death Cab for Cutie 161
Anything Box 160
The Cure 152
VNV Nation 139