I found a good touring book in the library the other day. It is called "Adventure Cycle-Touring Handbook" by Stephen Lord. It is a pretty comprehensive guide to touring that is broken up it 3 parts:"Practical Information" ie planning, bikes, equipment; "Trans Continental Route Outlines" brief outlines of different areas of the world written by cyclists that have been there; and "Tales from the Saddle" condensed journals of 10 different trips.
It is a brand new book so it is pretty up to date on equipment, bikes and geo-politics. Its worth a look for seasoned and first timers.
Its ISBN is 1 873756 89 5 and its website is www.adventurecycle-touringhandbook.com