Type Network — incredibly high-quality fonts by select independent foundries
YouWorkForThem — thousands of fonts in the “original creative marketplace”
MyFonts — thousands of fonts from all kinds of foundries, includes some trial fonts & free families. (good for searching and testing, but it’s better to buy through the foundries themselves!)
Great source of websites where you can find free fonts for your next project.
A great selection of tools that you can use to help you while working with fonts.