The Michelin guidebooks are excellent, particularly the Green book, although I don't know if it's the best for backpackers, or for Asia. Most guidebooks like Lonely Planet are no better than the rest, such as Let's Go, Frommers, etc. LP just happens to be the most famous, and that's usually for their Europe guides.
Even then, most of them are just good for basic information about the city and tourist attractions for when you can't read the local signs. That's why the map inside is kind of important. The hotel and hostel sections are always poor because they don't really list a great deal of them. You really have to go online to find more hostels. Combine internet research with the guidebook recommendations.
So forget the hotel and restaurant guides. You are buying these books to tell you the details regarding:
- travel etiquette.
- social etiquette.
- safety practice.
- FYI.
- good markets.
- cost of common, basic goods (so that you don't get ripped off by those who want to take advantage of tourists).
- decent maps for when you first get into the city.
- the background information and historical significance of some of the tourist attractions.
If the guidebook doesn't have decent maps for a particular country, then you'll feel a huge disappointment in your guidebook.
Some guidebooks like Lonely Planet will have a very good guidebook on Europe, but may not be good at....Australia, for example. You really do need to look inside the book and judge for yourself.
Check this out. Scroll down to the 2nd entry.