I was in the bookstore yesterday and came across this book. "2007 Photographer's Market" 30th Annual Edition. Published by: Writters Digest Books. Editor: Donna Poehner. 

It is a reference book listing where you can submit photos: ie: Consumer Publications (magazines), Newpapers, Trade Publications, Book Publishers, Greeting Cards, Posters, and Related Products, Stock Photo Agencies (no royalty frees listed), Advertising, Galleries, Art Fairs, Photo Contests, Photo Representatives, Work Shops & Photo Tours, Professional Organizations.  Over 600 pages. Just thought ya'll might be intereste!

And for those in the UK (or even those elsewhere, but who want to try to sell in the UK) there's the 'Freelance Photographer's Market Handbook 2007'

It's a bit thinner than the US one ... but then UK is smaller   

Anyway, it's a great reference source for the UK image market.