You have to DOWNLOAD fonts? Damn,i thought it was all there,just waiting to be discovered lol.^Nice one....
@shinigami8671: Just follow the tips killerdons gave you.
As for software, mostly Photoshop is used. You can also try Adobe Illustrator but I haven't used it for making signatures. Also try to collect some ideas from devianArt site. They have cool sigs along tutorials as well. At last for good Fonts you can download them from Dafont site. They have huge collections of fonts.