Hi Barbara, I'd suggest checking your local library for these titles.

The Craft And Business of Songwriting by John Braheny

The Songwriters Market (2007 edition won't be out until october)

Six Steps To Songwriting Success by Jason Blume

Getting a publisher interested in your song(s) is the way to go.
Just keep in mind, no legit publisher will ever ask you for a penny.

here is a link with some good info (a bit dated)
http://www.justplainfolks.org/ubb/Forum4/HTML/000276.html

Hope this helps