I personally like Canon. Their Canon Rebel XT is still around and I think is about 500$$ now. Very nice camera. I personally want the newer version: XTi. It runs a bit higher though.

It takes all auto focus Canon mount lenses, and I *think* the only difference between the XTi and XT is shutter speed or something? Nothing really big.

Nikon also has some nicer DSLR models. I do not recommend Sony though, since they ‘bought’ out Minolta, their quality has gone down, and their repair center sucks a big one, especially with warranties.
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Getting started, take a look at Olympus. Olympus cameras and Zuiko lenses were designed to be digital from the start. Many other camera brands started by using the old film based lenses adapted for digital use. These Zuiko lenses produce great results. Olympus cameras put the anti shake in the camera body, so it works with all lenses. I use an older E-300, and I am saving for the E-510. Olympus also has the dust reduction system which is better than other systems and a quick start up time. Olympus also is considered a better value because they a little less than other brands. The E-510 is an entry level DSLR for people who are not true professionals. Olympus has many features and would be in your price range.

Before making a final choice, check out some reviews at http://www.dpreview.com/.
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http://www.dpreview.com/

I’ve been brought up on Nikon products and can only comment on these products. I know Canon produces a great product, but the Nikon D40 runs about $400 on Ebay with a couple of lenses. If you wanted to bump up a little I would recommend the D80 and lens kit which runs around $1000 to $1200 depending on the quality of the lenses. If you had to chose between a good camera and a good lens, go with the better lens and work your way up.
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I am in a similar position, and I opted for a super-zoom camera, the Panasonic DMC-FZ50. Not a true SLR, but three conversion lenses and filters are available.

It features a 12X optical zoom Leica lense system coupled to the 10 Megapixel electronics. I think it was the first super-zoom to have a 10 megapixel CCD. Its image stabalization is excellent, an essential requirement in my view. At 12X it’s that or a tripod.

The 35mm equivalent of the optical system is 35-420.

I steered away from the more compact cameras. I like a bit of heft, individual buttons or dials for more than just basic settings, and an easy layout so i can keep my eye on the viewfinder while changing settings.

The camera has great features. Many super-zoom cameras do. They cover a lot of SLR territory that would require several lenses, all in one package at a much lower cost. I think they deserve consideration.

I like outdoor photography the most. I found that I also needed a compact, waterproof camera. Its fun to take a picture just as you paddle down the wrong side of the river, and handy to have a decent pocket camera you can stuff anywhere. I choose the Pentax Optio WP, the water-resistant rating provides for operation up to 10 feet underwater, It has been improved in newer models and I don’t think anything less is viable.

Good luck and happy snapping.
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Any of the entry level dslr cameras would suit your needs quite well. Canon XT, XTi and XSi are the most popular of the entry level cameras. The XTi and XSi both offer self cleaning sensors. Nikon D40 & D60 are both excellent entry level cameras.

You mention a wide variety of subject matter, so you will want to consider the different lenses you’ll be acquiring over time. Canon and Nikon both have the most available lenses on the market. As well as accessories. Remember, when you buy a DSLR, you are buying into a system of lenses and accessories.

Go to http://dpreview.com and compare the different dlsr models side by side, and see which features appeal to you, read the reviews. Before you buy, go to a real camera store, (not Best Buy or Wal Mart) and handle the different cameras, try them with different lenses, and get a feel for the camera.

Then go to a company like http://adorama.com or http://bhphotovideo.com and check the prices, both companies are reliable, and offer the best prices.

With your camera you’ll want an extra battery and a memory card of at least 4GB.
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pick nikon D40 or it’s 10mp twin brother D40x ,and keep your budget to buy extra lenses,such as nikkor 18-200 vr lens.
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At a range of $500, your best bet is the Nikon D40 with the basic 18-55mm lens to start off with. Later, add a 55-200mm VR zoom lens.

Just about everything else is outside your budget.

The Olympus cameras are worth some consideration, but they have a much more limited lens lineup and their 4/3-size sensor is physically smaller than the larger APS-sized sensor used in just about every other digital SLR, which makes for lesser performance. Olympus is a niche player whereas Canon and Nikon are not.

In any case, in your price range, it’s the Nikon D40 with lens that makes the most sense.
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