I'm almost sorry to bump a dead thread but I think it's important to note that Larabie doesn't allow embedded fonts - he specifically says that his license disallows linking/embedding via the HTML/CSS @fontface when it involves an unencrypted TTF file... which is exactly what ePub does... unless you've DRM'd the file.
Manfred Klein rocks. Just donate some money to Doctors Without Borders.
Typooasis hosts many of his free fonts and has a huge archive of other free fonts. Dieter Steffmann is interesting.
pdurrant: the likelihood of finding a "free" font that so closely resembles MT Baskerville is small. I wish you luck but when I searched for a free version of Parchment MF, I discovered they are all plagiarized ripoffs with minor changes. I couldn't (in good conscience) use them. This is one reason I've gone dormant. I was creating a 20-font ePub and ended-up having to replace most of my choices (twice in some cases) due to possible violation of terms of use. I ended up with 3/4 being MK fonts. God bless the man.