Are you thinking of general adventure, HOW TO, a particular destination of some general mix?
In the general adventure category group, I've enjoyed Barbara Savage's Miles from Nowhere mentioned above. Books by Jose Dew I found lighthearted and fun adventure stories. Books like Off The Map by Peter Jenkins inspired me. Joe Kurmanski has a fun style. Probably a bunch others as well...
I've taken some long trips and prior to going, I'll read a number of the books people have written of riding that area. For example, a search of online bookstore will give you quite a few accounts of people cycling across America. I'll browse the intro and look at the reviews as there is frequently an eclectic mix of styles and emphasis in these tales. Difficult situations make for more interesting storytelling so that might be over-represented, however I'll also learn from situations others found themselves in (either to get out or to avoid the troubles in the first place). No specific book to recommend here but not too hard to find...