@Psymon ---
The google fonts library and OpenFontLibrary fonts are ALL licensed for Distribution and Embedding --- Look for SIL OFL (Open Font License), GNU License, Creative Commons License.
Font squirrel offers almost all "Free Commercial", and many are ALSO DISTRIBUTABLE, and that is what you are looking for, right? You just must check the license for each font, and if they don't explicitly allow distribution or website/ebook embedding, you should avoid them to prevent hassles with the font creator.
Some other sources have great selections, but yeah, you have to check the licensing for each font. (daFont, FontSpace, the laTex catalog
http://www.tug.dk/FontCatalogue/, etc. etc.
If you upload an image of a font you like to WhatFontIs (font identifying service), they often suggest free similar alternative fonts. Again, you have to research the licensing.