K...

Kaven
Kazooie
Killer Carrot

L...
Lynx

M..

Magic card ( I compiled a tileset for him )
Martin Aka Party Dude ( I helped him with Carrottus Squash :P )
Mezz ( Some info from the book :P Age : 14 ( 1999) and lives in England :P )

N...
Nick
Ninja Dodo
Noogy ( Dean Dodrill, like you didn't know already :P )

O...
Onag ( famous for the Try Me Competition and his website :P )

P...
PhoenixB
Pikachu
Prowler

Q...

R..
Robert Allen
Rocky Raccoon
Recluse ( you might remember him as, the banner, I once joined his server, and he said hi, and banned everyone else, so he could play against me :P, He once banned me, cause he hit the wrong number :P, he use to be into Animorphs :P )

S..
Shadow ( not Shadow GPW :P )
Shadow GPW
Spaz
Speedy
Spiffy
Spy AD
SR AK CB
SR JP CB (aka Salamander =P =P =P)
Steel Talon
StevenT
Stripe
Sunny Girl

T..

Taylor -X, I remember him, I helped him make tilesets :P
The NEW SPAZ ( I still have his first set, stan *gins evilly* )
Turtle Slayer
Tweety ( The one from Turkey not the other Tweety, I once made a birthday tileset for her )
U..

Unknown ( I remember him from j2c I think )

W..
Wakeman is biased ( is Jazz2 Stuff still open ? )
Warlord
White Fang
White Rabbit

X..
Xeno

Y..
Yoshi ( he made some tilesets I think, there in my JSC somewhere)
Z..
No one's nickname began with Z back then :P

Hey Cell, for your Jazz2 Alphabet, you now have a name for Y, Yoshi