Each of these is a synthpop site unless otherwise specified. Please send me links to sites I missed. Please note the only site on this list that reliably posts mp3s is Blake's.. but hey, you never know. I even update mine once in a while.

Blake's Synthpop Page
-MP3 downloads, extensive track listings..still the best
Wave Fanatics
-HUNDREDS of New Wave MP3s for download.. nice
Liav's Synthpop Rarities
-MP3 downloads, impressively rare tracks
Bitboy's Hard to Find
-another page with MP3 downloads
Paul's Synthpop Page
-MP3 downloads..good selections
Kraftwerk Media Center
-Kraftwerk videos and MP3s
Robert's Rare Synthpop
-MP3 download.. another good page
YARST
-MP3 download.. I'm running out of things to say...
Record Crate
-MP3 download.. I quite like this guy's taste
Music Club Remixed
-amateur remixes in Realaudio + MP3 download
Euro Spin!
-extensive Euro selection, Realaudio only
The Great Commandment
-MP3 downloads and synthpop webcasts
Radio Wave
-MP3 download, focus on New Wave
Just Another Synthpop
-MP3 downloads and webcasts..
MP3 by Request
-MP3 download with eclectic range of genres
TD New Wave
-MP3 download with a New Wave focus
Wave of the Week
-MP3 download..focus on 'Eighties' music
Synthpop Network
-A very complete index of synthpop related sites
A Different Drum
-Online record store: 'the source for synthpop'