My old comrade-in-arms Peter Eltringham tells me the new 2nd edition of the Rough Guide to Belize is hot off the presses. In fact, I just got a copy Peter mailed me this morning -- not exactly sure when the book will be in bookstores and on Amazon.com, but should be soon.
The new edition has a blue cover and has a photo of the Blue Hole on the front. It has coverage of Tikal and the Bay Islands of Honduras as well as Belize.
Peter first came to Belize years ago with the Brit Air Force and has spent a great deal of time in the country since, probably more than all the rest of us Belize guidebook scribblers combined. He has done a number of Rough Guides besides the Belize edition.
His books are all thoroughly researched, and I can highly recommend it.
Belize First Magazine http://www.belizefirst.com/
Belize First Guide to Mainland Belize
Fodor's Belize & Guatemala Guide
UpClose Central America