I asked a similar question either last week I think. But anyways....
Here is a link that I was provided with:
http://www.capsu.org/wow/fish/kalimdor.html
This info was provided by Khalane - Guru.
Just keep on fishing. From what this link shows you and I both will be spending some time in Tanaris lvling up our fishing skills. You will also need some baubles....lol. If you are Horde on Zuluhed look me up. My alt will be supplying me with baubles.