Its not a 128 or 64, but theres a really good VIC forum over at:
http://sleepingelephant.com/denial/
Reason I bring this one up is that there appears to be alot of 6502 coders there, so there's alot of interesting ML tidbits in the programming forums.
Looks like a well developed community, and some of our regulars are members there.
I love Denial and whether you are or were a VIC-20 user or not, drop by and say hello. There's lots of interesting discussions and if you can believe it, there is still new hardware and software being developed for the VIC-20.
Since I seem to be stuck with a whole library of VIC-20 books I didn't really want in the first place, I assume I'll pick one up eventually. Back in the day I bought one on closeout for my daughter so she wouldn't pout when I took over the C64. :)
You still have those books, eh? We should work something out.