This new book by Roger Dymock has just been released (got my copy in the post on Saturday). Its a good all round reference and introduction into most facets of observing these objects from Visual to CCD (and DSLR), Astrometry to Photometry and Occultations. If you want an all in one, up to date, general reference/guide on this topic then this book is a good buy.
http://www.springer.com/astronomy/as...-1-4419-6438-0
http://www.amazon.com/Asteroids-Plan...0979817&sr=8-1
Cheers