Michael Levine's feynman bundle for drawing the diagrams in LaTeX 2.09 is still available.
Thorsten Ohl's feynmf is designed for use with current LaTeX, and works in combination with Metafont (or, in its feynmp incarnation, with MetaPost). The feynmf or feynmp package reads a description of the diagram written in TeX, and writes out code. Metafont (or MetaPost) can then produce a font (or PostScript file) for use in a subsequent LaTeX run. For new users, who have access to MetaPost, the PostScript version is probably the better route, for document portability and other reasons.
Jos Vermaseren's axodraw is mentioned as an alternative in
the documentation of feynmf, but it is written entirely in
terms of dvips \special commands, and is thus rather
imperfectly portable.
An alternative approach is implemented by Norman Gray's feyn package. Rather than creating complete diagrams as postscript images, feyn provides a font (in a variety of sizes) containing fragments, which you can compose to produce complete diagrams. It offers fairly simple diagrams which look good in equations, rather than complicated ones more suitable for display in figures.
This question on the Web: http://www.tex.ac.uk/cgi-bin/texfaq2html?label=drawFeyn