I've got the Fourth Edition of Van Allen's and Mallis' book. I figured I'd go through my Morgan and Peace dollars and determine what the VAM variety was for each. So far two tries and I didn't even get far enough to consider myself a failure. Maybe I should have started with some of the simpler ones. I first tried an 1880-CC. Today I tried a 1878 7tf. Now I'm beginning to think it can't be done because it's all bogus. I can hear all the numismatic insiders laughing at me because I fell for the joke.
It can be frustrating, but the easiest way I found to do it is to look the coin over for anything that is obviously not normal like die breaks/cracks/chips or grease filled dies. Another big one is doubled dates and spikes and dashes around the date. Then look over the VAM listings for things that match what you have found.
If you REALLY want torture, try to use the Isegrim database. It contains a rather extensive listing of the Roman Provincial and Greek coins of Asia Minor. Its poorly constructed to begin with and, to top it off, is in German! If you dare: http://hist3-10.phil-fak.uni-duesseldorf.de/isegrim/db_am_r.php3?tan=796322gRNQCO6l1po&B_X=1&B_F=0
I agree, first look for anything out of the ordinary, then use a loupe to check the date, that's usually a very common place for VAMs. If you don't see anything that stands out, then go to the book and look over all the possible attributed VAMs. Of course it could always be a unattributed one too.
I've got a Second Printing (1977) of the 1976 copywrited version. I was smart enough to not even think of trying to use it. Only good(?) thing about it is that it's autographed by Van Allen (for what that's worth).