(Canon sources only, please)
With the attitude toward canon on this forum, that's pretty severely limiting. According to some on this forum, bathrooms don't exist because they've never been seen or mentioned in canon. Absolutely no inferences allowed.
So going strictly by canon, Earth and Vulcan are just about the only Federation planets that we know of. The other 148 haven't been named.
Come to think of it, Earth might be debatable. Has anyone outright said "Earth is a Federation member" in those exact words? If not, that's not canon either.