If you're a die-hard baseball card collector, The Standard Catalog of Baseball Cards is a reference tool you must have. Granted, our company publishes this massive reference guide (the 2008 edition weighs in at 1,850 pages), but corporate plugs aside, it's the most complete guide to baseball cards on the market and offers complete checklists of some very obscure sets.

The current editor of the Standard Catalog is Don Fluckinger, who is also a regular contributor to Tuff Stuff. Don has a fascinating blog where he posts information about the newest sets that have been uncovered. It's hard to believe that there are still sets and cards that are just now being discovered decades after their release, but that's what makes this blog so cool. Plus, collectors like you often provide some valuable information.

To check it out, click here.