I'm just about to start DMing again as of this Monday, and so far my campaign will include the following books (this is our first foray into non "core only" 3.5, so it should be interesting):
- Core (PHB, DMG, MM)
- PHB II
- UA
- Miniatures Handbook
- Spell Compendium
- Heroes of Battle
- Heroes of Horror (possibly,not yet confirmed)
- Homebrewed campaign material (setting, monsters etc.)