Bolt patterns

[tehp@qualmedoregon.com]

Someone please point me to a FAQ or provide me with enough
info to make my own:  I want the whole skinny on what Audis
from 1980 to present had in the way of bolt patterns, and
how interchangeable their hubs/rotors are.  I am having
trouble finding wheels to fit my 4x108 4ksq, and if you know
of aftermarket custom wheels that are available in this
size, then throw that in too.  I've had thoughts to alter
the hubs/rotors, buy expensive wheels in 4x108, switch to
UrQ hub/rotors, and anything in between.  What works?  My
reason for wanting to know what bolt patterns everything
else has isn't just for putting them on my car, but also
whether or not I would be able to use 4x108 (A.K.A. 4x4.25)
on my next Audi down the road, most likely a 90 20v quattro.