Aside from Avalon's Gate, available on Kindle, Geoff King has written two best selling non-fiction books. The first of these, titled The Secrets of Selling http://amzn.to/zqPY1W is published by Pearson plc (part of The Financial Times Group.) Now in its second edition it has been translated into nine languages and is consistently popular worldwide. It teaches people the tips, tricks and techniques to sell well in almost any situation.
The second, also published by Pearson, is Brilliant Baby Names http://amzn.to/A5i7JS. This is too in its second edition and differs from normal baby name books in that it looks at the psychology behind names. Your name can affect your life chances considerably and this book shows you how.
He is writing a follow on to Avalon's Gate but for the moment...that's a closely guarded secret!