I've just been playing with stork's DOAP-a-matic and viewer ( crschmidt has a good note on these tools). Couldn't be easier. So I've added a DOAP profile to the Atom/OWL and PRJ (new name please!!) pages.
I've got material on three different domains (here, ideagraph.net/ http://purl.org/stuff and semtext.org - the same HD locally) and with RSS, FOAF and now DOAP as the primary function. Could really do with a seeAlso management tool, i.e. a pocket RDF editor which will also remember local file/remote URI mappings.