Good Books for a DM (D&D 3.5/D20 Modern hybrid)

[enigmatime]

Okay, so I'm writing up a campaign currently and it is sorta a mix of D&D 3.5 and Modern. It is probably going to have some time travel and what not (I can't say much because a few of my future guinea pi- I mean players are on the forums).

The list of books I currently own are as follows (all 3.5 except Pathfinder):

The essentials (PHB, DMG, MM I-III & V)

Forgotten Realms Campaign Setting (Faerun or something)

Complete Arcane

Pathfinder

Pathfinder Beastiary

Deities and Demigods

BoVD (PDF File)

BoED (PDF File)

Book of the Planes (PDF File)

Elder Evils (PDF File)

The Homebrew Section of the Forums (I don't own this but, you know, it's there)

There are a few other books that I own but they are in my closet and gods forbid I go in there...

Edit: I'm going to a few bookstores and gaming stores today, so I'll add whatever I get when I come back.

Edit: Chronomancy: The Power of Time

Edit: I forgot to ask... *facepalm* Does anyone have any suggestions?