Adding fonts?

Hi everyone! I just started teaching myself how to use the GIMP last week or so, and I'm doing fine so far, got all the basics down (no small thanks to some of the excellent tutorials posted to this community!), but I'm finding myself desperately font-less! I have only the boring ones that come with the programme itself, and though I've found additional fonts online and put them on my computer, I have no idea how to add them to the GIMP! I tried to find some sort of upload section, I even tried cutting and pasting and dragging--all to no avail!!

Oh, help me, gimp_users! You're my own only hope!