I think I've got almost everybody's most wanted below. If I missed something, just add it to the comments!
T_s - homer (did you ever get one?)
Philipilihp - mclaren f1 GTR
El_Uly - Toy Yodas
JMildren - 240Z's, red Toyota 2000 GT, Cool Classics CRX (will trade multiple cars for this), and Datsun 620 in blue and/or orange
Walfisch - Japanese cars, in particular a 510 Bluebird and a Kenmeri Skyline. Also, Homer and a Snoopy.
Frosted - JDM, yo.
Round badge - Zamac 70 Chevelle wagon, 67 Chevelle SS 396, Ford Falcon V8 Supercar, Datsun 510 wagons
iDSi-Guy Fiesta TH (2013 & 2014), teal civic, Tucker Torpedo (anything, but esp. the$TH version), LR Defender (Matchbox), Z4 M ( Black and White ) any, ANY Takara Tomy ChoroQ Zero line. Hudson Hornet.
Enginerrrrrrrrrrr - White porsche 993, Curiosity Rover
Fintail - old stuff!
Carnage - Tucker Torpedo, Blue Datsun 620
Daender - Greenlight 2008 Ford mustang GT, pikes peak Celica
Sn210 - BMW 850, gold Delorean, 2004 Shelby cobra concept
CyborgAbe - MBX CTS wagon, all the wagons for wagon quest