Writer's Guidelines from Writing for Dollars
or write an article for Writing for Dollars Guidelines
I haven't tried this database of magazines, save for poetry, but it looks interesting. duotrope digest
Science Fiction magazine Neo-Opsis will be accepting new submissions May 1, 2010. Guidelines.
Nota bena: It's always a good idea to check out a magazine prior to sending in a submission. Is it the type of publication that suits you and your writing?