Jim,
You can also check Jim Quinn's site:

http://members.cox.net/silverstrikes/
He has which of the casino's has strike machines. And what silver strikes is in the machines at present. And where they are located in the different casino's. He tries to keep the site updated as recent possible.
Between this and the Sliverstrikers site. I think you can find out just about everything needed.
Happy hunting,
Dan