Detailed English language information about Hampi is quite limited. Apart from the Lonely Planet book on India, which has a brief if quite useful introduction to the area, there are precious few travel guides to Hampi. On the other hand, a number richly illustrated books on the monuments and history of the Vijayanagara Empire have been published, though these tend to be quite expensive as many are out of print. Check out Amazon for more information.
The most useful books I have read are Hampi, by John M Fritz and George Michael, published by India Book House PVT Ltd, and Hampi Ruins Described and Illustrated by A.H. Longhurst. Although published nearly 100 years ago, the latter still provides an incredibly rich description of the monuments themselves and the history, religion, and culture of the area.
If you are a real history buff, you should check out Robert Sewell’s ground-breaking A Forgotten Empire, which features a detailed history of the rise and fall of the Vijayanagara Empire and is accompanied by the first English translations of the descriptions of the capital by the two Portuguese visitors, Domingo Paes and Fernao Nuniz. A copy of A Forgotten Empire can be downloaded in a variety of formats from Project Gutenberg.
There is some information about Hampi on the web, though much of it is quite fragmented in nature. The most comprehensive site about the area I have come across can be found at: http://hampi.in/. Another excellent site for people interested in the history and archeology of Hampi is http://www.vijayanagara.org/.
Do you know of any other books or websites covering Hampi that you would recommend? If so, please drop me a line at richardbrownatvia.com.tw or post a comment below.