There is a lot of material that I ban including stuff I don't own. Off the top of my head:
Core:
-Halfling Riding Dogs
-Orgosh's, Spiked Chains, etc.
-Most alchemical items
-feat: natural spell
-about a dozen spells (for current campaign)
Supplements: Most of these I don't own, but I have read in the bookstore
Book of Exalted Deeds
Book of Nine Swords
Expanded Psionics Handbook
Magic of Incarnum
Race of [x] almost the entire book except a few spells and the expanded skills
Complete Warrior: the base classes and a few PrCs, feats, and items
Other Complete Books: nearly everything except for the spellless paladin and ranger variants from Complete Champion and few of the following: PrCs, feats, spells, domains, and magic items
Players Handbook 2 except for the fighter variant, druid shapechange, some feats, and some spells.
Spell Compenedium 50-75% of the spells and several domains. Will probably become the entire book if and when I switch to Elements of Magic for the magic system.