I used to collect coins when I was a kid, and the Blue
Book (wholesale
values) and Red Book (retail values) were my bibles. Coins had a pretty
good grading system, and you could find fairly reliable production data.
I don't know of anybody that has tried to do anything close to this for
computers.
I have "A Collector's Guide to Personal Computers and Pocket Calculators"
by Dr. Thomas F. Haddock that attempts to price old computers. They
don't do a very good job, though. According to the book, an Apple IIc is
worth $200 - $400 and a Lisa 1 is worth $50 - $150. To be fair, though,
the book is from 1993. Anybody know of anything more recent?
Tom Owad