On my regular missions to pillage as much old skool as my connection will allow, I find a lot of good shit - much of which I keep a secret and don't share. But I am not a totally selfish fucker - especially when it comes to good DJ mixes (which are harder to find than you might think)...
Obviously, there is Tim Acid's The Acid House - he regularly puts up good mixes, mostly focused towards Balearic or proper late 80s acid house. If you've not visited, do yourself a favour and git over to it...
Then there is Californian DJ Ellis Dee's site - it's not too pretty to look at, but all the mixes I've downloaded have been worth the effort (but mind out, not all are old skool).
A Jackin Phreak is someone I've only just discovered; he's French, but I'm not going to hold that against him too much. Doesn't look like he's been that active for a couple of years and that's a shame because this guy knows his old skool acid house; his mixes are laced with obscure gems as well as the classics and he combines them all rather well with contemporary tracks of complimentary flavour. Hot stuff.
Even better, the dude has produced some great revivalist acid house and hip house that you can preview here before buying/stealing elsewhere.
Other acid house revivalists include Kings Of The Universe, and much of their work is available for download on Soundcloud. I quite like their remake of Tenaglia's "Music Is The Answer", "Acid Is The Answer" - because if dropping acid isn't the solution, then dancing to it always is.
Oldskoolmixes.com is a bit out of date (seemed to have migrated to crackbook), but still has plenty of good stuff to find - although because a lot of the mixes come off 20 year old cassettes the sound quality can be quite shitty. A pity, because the DJ Hype pirate tapes are really quite entertaining.