Karen Armstrong is probably the most popular writer on religious topics in the UK. I found her book on Buddha to be very helpful as an easy and short introduction.
Nhat Hanh has a dozen or so other books that are IMO just as worthy for beginning study.
I've also found The Vision of the Buddha by Tom Lowenstein to be an excellent comprehensive illustrated book on the history of Buddhism and it's formation into the varying schools of Theravada, Mahayana, and Vajrayana:
I also have a few admonitions, but as they're all from the Zen aspect of things I'm not sure how useful or relevant you will find them... Ahhh well; onward, to the linkage-posting-thingie!
published by Harper, ISBN 0-06-251294-3 A very easy to read and understand explanation of the Buddha's first teaching. Sylvia uses stories and examples to explain the four noble truths and eight fold path.