I'm listing here some services I think you should know about.
Gerg Shepard of Stark House Press has scanned several of my old novels for re-publication. They were scanned and proofed with 100% accuracy and the prices were far below equal services I found elsewhere.
Crimespree deserves much more support in the States. While it's popular in Europe, it doesn't have much of a profile here. I always find two or three stories per issue strong enough to consider for reprint in our annual Best Of anthology. Plus it's beautifully made.
Over the years I've probably dealt with a couple dozen different internet used booksellers. My complaint about most of them is that they never mail when they say they will. I've paid priority rates for books that weren't mailed for two weeks. I once paid $80 for a rare paperback that literally fell apart in segments when I opened the cover. The exceptions are--I'm glad to say--all the mystery bookstores and (for general books and magazine including pulps) Pandora's Books.
I've had so much trouble with small indy suppliers that I now stick to Amazon and Barnes and Noble. If you've had good experiences with others let me know, especially if they offer better rates than the big two.