Illegal and legal use of pictures.

Unfortunately, using pictures off DeviantArt or Google without the artist/photographer's express permission(and this does NOT mean saying "I got this off such-and-such a site, here's a link." You must actually speak to the artist himself and get permission to use his work) is ILLEGAL. The following sites contain high resolution stock photos for anyone to use. You don't have to ask anyone for permission and you won't be breaking the law.

http://www.bigfoto.com/
Use the drop-down menus along the top to access hundreds of large, high quality photos of locations around the world.

http://www.freedigitalphotos.net/
High quality small to mid-sized photos. Must pay around $0.20 for large versions of photos, but the smaller, free versions will work for most MAB-related art.

http://freestockphotos.com/
A lot of variety and the photos are quite large. Many images have people or animals in them.

http://www.stockvault.net/
High quality photos, all very beautiful. Small to mid-size, with some larger ones thrown in. Perfect for MAB artwork.

(Thanks emptysaucer for pointing this out.)

Deviantart.com also provides stock photos. There is a category for them.