DeviantART: a photography, drawing, and painting hosting website. Images are tagged for easy searching. Free to use.
Flickr: a free photo sharing site created by Yahoo!. Upload high quality photos, share them, and tag them for searching.
FotoFlexer: an online photo editor. You can upload photos from your computer or use one from Photobucket, Facebook, Flickr, and more. Free to use.
Photobucket: a free photo hosting website. It provides you with an embed code so you can plug your photos into any html-based page. You can also make your albums private, so that they will not show up in a search.