heya, i work in a photo studio and we use canon eos 1d mach 3's but at $13500 just for the body it's well out of anyones price range.
i found it hard to go down in quality but eventually got a canon 40d that cost me jsut under $3000 with some extra gear and that was over a year ago. i can say this is a very good camera but probably still too much for an entry level enthusiast. here are some full size pics i have been playing with recently (note the 1st link is staright from the camera but the 3 after have been edited with photoshop for different effects, they will probably appear a little bit grainy due to the sharpening effects I have been using lately)
http://www.shaun-maluga.com/Images/Mini/IMG_1994.jpg
http://www.shaun-maluga.com/Images/Mini/IMG_2178.jpg
http://www.shaun-maluga.com/Images/Mini/IMG_1980.jpg
http://www.shaun-maluga.com/Images/Mini/IMG_2067.jpg
the 400d/450d's are great entry level dslr's like everyone has suggested. definitly worth the money. only complaint would be that im a pretty big guy and it felt a bit small in my hands, but that would be about the only complaint at that price range.
the issue with these dslr's is the size. i really only use my camera when i have really planned to, not really a happy snaps at a party kinda camera. if you want something a bit more compact and user friendly the canon powershot g9 is a great camera. a guy i used to work with uses one, here is his flickr stream...
http://www.flickr.com/photos/gabeveit/with/3230462682/
basically i would advise that if you want to get into photography and learn a few techniques and get a little creative every now and again then start with the 400/450d. if you want something that you can have on hand and take some nice photos of your life then go the powershot.
if you get into and want some photoshop advice then feel free to drop me an email