This is it....the AD&D rulebooks for 1st edition are starting to appear on dndclassics.com. the Player's Handbook is now up, so the DMG and MM must not be far behind.
I've said it before, and I'll say it again: this is a very good time to be a fan of the classic editions of D&D.
Now....will they put up the OD&D reprint in PDF eventually? That would be cool.
Anyway, in case you didn't know it, you can already find the Fiend Folio, Monster Manual II, Manual of the Planes, Deities and Demigods, Wilderness Survival Guide, Greyhawk Adventures and Oriental Adventures in PDF on dndclasssics. So....once they get the DMG and MM up, along with Dungeon Survival Guide and Arcana Evolved I think all of the 1E hardbacks will be available in PDF format.
FOLLOW UP: It's a clean, fully-book-marked PDF, very readable, of the reprint version of the book (as expected from the cover above). It's also a tiny file, under 6 MB in size...I picked up the L series modules while I was at it (Secret of Bone Hill and its two follow-ups) and some of those were several times larger in size...go figure.