I bought William Cohenour's "Comprehensive Nevada Silver Strike Reference Catalog". It lists the approximate silver weight of each strike, when it was released and the $ value. He updates it continuously so when you order the catalog everything is current. I sold over 250 strikes on using his reference information as part of my ebay description.

His Classified Ad is here:
http://www.silverstrikers.com/Web/Main/Classified-Ads.php/