Depends on exactly where you interests are. If you are interested in early glass, my book is available to mrmbers of the Forum for $16.00 plus either $2.00 for media mail (the slowest) or $4.00 for priority mail. It regularly sells for $20.00 +++ plus postage, etc. It is The Collectors Guide to Civil War Period Bottles and Jars --- 3rd Edition. This book has chapters on manufacturers, digging, etc., plus individual chapters for Bitters, Beverages, Inks, etc., and includes many photographs and illustrations.
You can order it directly at my address: relicshop@ncol.net .