In Portland, Oregon we have a very strong following for the older Volvos, 122, 544, 444, and even the forgotten 140 series!
A favorite resource of mine is the Portland Round Fender Group on Yahoo. We have monthly get togethers... you have to ask to join however, and of course if you don't live in Oregon or Washington, it might be difficult to attend! Find us at:
http://groups.yahoo.com/group/PDXvolvos/
By the way, here's our baby (bare-metal, complete strip-down resto)...
Before:
As she sits now:
More photos of the restoration at:
http://www.flickr.com/photos/flynhwn7/sets/72157629321223592/
EDIT: Sorry, didn't read all the posts.
I recommend going to Olof at Vintage Import Parts (
http://www.vintageimportparts.com/used.htm) or Mike Dudek at iRoll Motors (
http://irollmot.ipower.com/oscom/index.php?cPath=26&osCsid=3f53e2c2a56a7d84277b8fbcd39ab73c) for new parts. Between the two of them, you should be able to find most replacement parts, including seals, trim, and engine stuff.
If you're looking for OEM stuff, and don't mind it having some of that "original patina", contact Chris Horn (who lives here in Oregon). PM me for his contact info.
IPD used to stock performance stuff for the B18/20, but it might be worthwhile going straight through Isky or other performance houses to avoid their markup. Interestingly enough, Galen (oldschool) found performance solid lifters on the Jeg's website for WAY less than other competitors, but you have to buy the kit for the V8, which means you end up with double the amount of lifters (go in half and half with someone else and score!)
Agree with Andrew... have not heard good things about VPD.
If you want to lower your 122, I suggest a spring kit. Several outlets stock them, including those stateside and in Europe. If all else fails, measure the diameter and dimensions of your stock springs, and order them from Summit or Eibach.