I use Duotropes Digest for market search. It is a free searchable database fro poetry and prose. You can sign up for a newsletter of poetry or prose - which sends you handy clickthrough links. While you are on the site donate to help them along. You can see by my CV I have done well using Duotropes.

They have criteria which weeds out markets that are not good for the writer (scams set to fleece you). I use it in two ways. I check the submissions calendar and write for a particular market and I search for markets that might suit something I have written. I have had a large amount of work published by finding ‘my’ markets. There are plenty of other market databases around and they are all useful. I just find Duotropes can be tailored to my needs by that little search engine they have.