The two definitive guides to chips from Nevada are "The Chip Rack" and "The Official U.S. Casino Chip Guide. Your chip is listed in The Chip Rack as a "C" chip with an estimated value of $5-$9. There are a number of online sites for identifying chips but value guides are frequently only available in print form. Some of the guide books are available through the Museum of Gaming History -

http://museumofgaminghistory.org/mogh_home.php