I'm seconding SBFR's Fan Disc series, but it would be better idea to buy them directly from the circle's online store.
They're pretty cheap, international shipping wasn't too bad, supporting the fandom is (generally) a good thing, they come with neato extras on the disc (art, fanfics, wallpapers, and even a flash game on the third) and I don't know if anyone's uploaded 3.5 yet. Also, doujin circles do tend to get rather upset by piracy and keeping good relations with the Japanese fandom is very important (and pirating small-scale independent works like this kind of a jerk move). I own all four as well as some of their other albums, so I can provide pics if anyone wants them or other info. Here's another rec, this one is free.
I'd throw money at this guy if he did a physical release.Here's one by PengoSolvent.
There's a download in the description.
I've seen a few more fan albums. There's the TO DREAM series, but I need some more info on them. I know there are at least three of them and they've been released for Comiket. I also know that the fellow who did them is part of an upcoming fan book+disc set. There's another one I saw on Alice Books (note: not linking since some of what they sell is NSFW), I think that one comes with a book as well, but I haven't bought it yet since I my income is whatever I get for holidays and Alice Books can be a bit pricey due to shipping. I'll post about anything else I find.