Try and get a good solid base, get yourself a few Rolling Stones records (or just invest in "40 licks" as a starter)
Try and get a couple of Led Zeppelins albums if possible, maybe a little ACDC.. get a decent feel for classic rock first.
Definately pick up "Too Much Too Soon" from the New York Dolls, "Rocks" and "Toys In The Attic" from Aerosmith.
From there, the thing I've found that works is this..
Find a band like Poison for example, read up on them at Wikipedia, check which albums charted well and buy a couple. See the bands they went on tour with, read about them, see which albums did well, etc etc.
It's weird but the linking system works well and it'll tell you "after that they made a move to industrial music and the singer became a goth" *cough Jani Lane cough*
Oh, get Too Fast For Love by Motley Crue by the way. I know you're already into them. If you've already got it get it again, that album is probably the best 80's rock album that came out, aside from Appetite.