I do this with the online d20 srd and it's free.
Don't get me wrong; I love the d20 on-line SRD. Used it almost everyday. But imagine that online d20 SRD with every monster, magic item, NPC, class, feat, etc., ever published by WotC, in any book, magazine, or web enhancement. With an encounter builder. And a monster creator.I do this with the online d20 srd and it's free.
To confirm what darjr said; right now you'd only be missing out on the Character Builder. Everything else is web-based, or (in the case of the magazines) PDFs.Still, the Mac issue rears its ugly head again. I use a Mac, so what parts of this great functionality would I be missing out on if I wanted to get a subscription?

Open Grave will probably be added next week, assuming they stick to their monthly update cycle.It's drawing from every Dragon article, Dungeon adventure, published adventure, and every source book sans Open Grave.
Hrmm... OSX is built on a BSD clone... I wonder if the Wine emulator will compile and run on it...That said, I use a Mac, and I confess to buying VMWare and a copy of Windows XP just to be able to use the character builder.![]()

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.