Four guidebooks to the latest games, Pokemon HeartGold & SoulSilver were announced on the official website. The guides cover all the aspects of the games including: game walkthroughs, maps, the Pokeathlon events, the PokeWalker, the Safari Zone, moves, events, Pokedex, and more.
All four guidebooks go on sale in Japan on October 1st, 2009.
Source:
http://www.pokemon.co.jp/goods/book/