I've got a 4 year old Canon Rebel XT, and I love it. I think the XSi is about $500, maybe 600 or 650 with a basic lens. IronMan77 is right: it gets pretty expensive. But I love photography and love my camera so the price is worth it. Check out
this site for product reviews and info.
Wired.com also has a lot of good reviews of new products. I personally prefer Canon, but some people prefer Nikon; these two companies are the leaders.
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