The logo font, Runic MT Condensed, does in fact have lowercase characters. The thing is, it's kind of unsuited for reading for long periods of time. It'd be serious eyestrain. Not to mention, the in-game font needs to have similar proportions to the current in-game font to work right, which Runic MT Condensed most certainly does not.
Dafont.com has a font called "Final Fantasy Font" which seems to be based on the logo font, but it's not nearly as good, it's a poor imitation, and it's missing a ton of elements from the original font. I strongly advise against using it for pretty much anything.