Casino Chip Price Guides tend to not go on sale and tend to keep the set price every where. The only differential is when you do mail order or buy on-line. Some places charge different shipping/handling costs.
If you are looking at Price Guides for Nevada, there are only two current guides. The Chip Rack (TCR) in an tabular layout, list all known Nevada releases. This means, NCVs, roulettes, LE's, rack chips, and more. The "Official" Guide includes Nevada, as well as New Jersey, Colorado, and many of the Riverboat States. It is a mixed tabular layout accompanied by some pictured chips (each page can accomodate the listing of about 40 chips, while each page contains a photo of eight different chips. This guide only lists rack/house chips and some roulettes. No LE's.
If you are looking for other Guides, there are publications for Califorina Card Rooms and an annex for California Indian casinos, Riverboat casinos, Atlantic City, Puerto Rico, Montana, Crusie Ships, Caribbean and Illegals.
I don't have links readily available. However, I suggest you visit
www.thechipboard.com and post this same question. Be sure to include your email addy and use your name (you've been through this before

). Also, be sure to state what geographic area you are interested in. I suspect you will be contacted by several sellers.
Jim (Gaming Ore) Follis