Andy,

You can get great sets of chips on Ebay for much less time and effort than it would take you to canvas an entire area. Here is a link to all my Chip sets in my Ebay Store. You'll find chips from Mesquite, Primm/Jean, Las Vegas and when I can get to Laughlin again, Laughlin. :O)
http://www.stores.ebay.com/lasvegasgifts/plistings/list/all/dept1/index.html

I am also listing each chip in its own auction along with a picture of the casino! I'm not quite done, but here you go. (G)
http://www.stores.ebay.com/lasvegasgifts/plistings/list/all/dept6/index.html

I would also agree with some of the other people that have posted to you. Try to get extra chips from the casinos around you and then trade with people.

Viva Las Vegas,

Byron Allis :o)