If you want to gain a good, introductory level understanding of the economic underpinnings of different types of auctions this is the book. Hubbard and Paarsch distill volumes of research into methodical examinations of optimality and strategies in different auction types, when these types of auctions are useful, and what factors tend to influence their outcomes. If there's a gap here it's in the sidelining of psychology and irrationality that humans exhibit. There is some discussion of that when considering auction types whose rules are too complex, but I would've liked to see that get a bit more coverage.

That being said, auctions are an essential economic structure that influences many areas of business and society today. I highly recommend this book as a solid first step into understanding them