Hello, Gene Florence writes many books on depression glass. I own several editions myself and they have great pictures, descriptions with sizes and estimated values. Here is his latest book http://www.amazon.com/Collectors-Encyclopedia-Depression-Glass-Florence/dp/1574326279/ref=sr_1_1?ie=UTF8&s=books&qid=1265383337&sr=8-1
but you usually can pickup an older book for $5-$7. I'm not sure where you located but most libraries have one or two copies of his books. Thank You Tom Please click accept.