The following sections define various encodings as PostScript encoding vectors. These files can be installed in the Dvips header directory and then used in psfonts.map to change font encodings of downloadable or builtin fonts (see psfonts.map).
You can also specify these .enc files to Afm2tfm when building a font (see Changing font encodings).
For a discussion of TeX font encodings in general, and defining new ones for use with fontinst in particular, see http://www.ctan.org/tex-archive/fonts/utilities/fontinst/doc/encspecs.
A tutorial on character code issues in general is available at http://www.cs.tut.fi/~jkorpela/chars.html.
Naming specific characters is a tangled and difficult area. Here are some links to character tables for Unicode, Adobe, and WGL4, for your researching pleasure (thanks to Boguslaw Jackowski for the list):