Spink's Standard Catalogue of British and Associated Orders Decorations and Medals With Valuations by E. C. Joslin (1984, Hardcover)

Very good 1984 intro book for the British medal collector. It definately help you identify various medals and you will be able to readily identify the major variants. While the valuations are quite old, it helps you to plot the market and provides good historical background. This should be considered a fairly basic book for your library and possibly one of the first you should buy.