Well, there's self-publishing, whereby you put out a book or tape, but "real" publishing, whereby someone else takes a flier on your words and music, and tries to "place" the song with a performer or two, that's a different thing. For lots more info than you need, try rec.music.makers.songwriting (a newsgroup) or do a search on "songwriting" or "songwriter" on the web, and settle down for a few months of reading (assuming you look at every site).
I personally haven't had any luck with my songs, but then I haven't tried all that hard to find a publisher. It depends on the style, too -- rock songs are harder to place than country, since so much of rock music is self-produced (i.e., performer-written), one cause of the [sarcasm on] high level of quality we see in rock music today. [/sarcasm off]
You can try a web-site, too, like mine, at
But it won't get you much more notice than you've had so far.