No, you can't use WoTC art for an E-Book... I do recall seeing a site that was intended to allow cheap, one-time access to decent art. They were pretty decent quality pics, done by people who have done some work for major third party publishers. I'll look around for the link.
Other than that I'm not aware of any fantasy stock art sorts of sites.
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"I hurt Firewing." is not something a huge number of people can say. "He dropped a parking garage on me," on the other hand, a lot of people can say. -Kazan, my Champions GM. | 
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