http://www.lecb.ncifcrf.gov/~toms/latex.html#latex.tex.resources
see: Conversion between Formats, RTF, latex2rtf.
There is also information at http://tug.org/utilities/texconv/,
maintained by Wilfried Hennings.
(Tom, I wonder if you and Wilfried could somehow collaborate to avoid
duplicating effort ... or maybe it's not worth it. Just a thought.)
k