However, I've shot the Nikon's and Sony's enough to tell you that there are decent choices there as well.

If you go Canon, the Rebel Xsi and Xti are both recent good choices. Resolution, image quality, iso, lens choices, AF speed and reliability are all good.

If you go Nikon, the 5000 is the best choice. I have yet to talk to someone who doesn't shoot for more than a passing hobby that has not been extremely pleased with the camera.

Everyone above already gave you the skinny on the Olympus. Stick to one of the big two.

Whatever system you get, go ahead and get the kit lens that comes with the camera in the VR or IS version. In Nikon, the lenses that have a motor inside of them to correct camera shake and give you a sharper picture are called VR. It is worth every penny. The Canon version is called IS and same thing.

When you want a little more reach, both camera systems offer an inexpensive 55-200 stabilized lens. Yes, a couple hundred bucks for the extra zoom lens is a chunk of change, but it is worth it.

I've bought used lenses from friends and even people that I've only met once, but I've always been able to hold the glass in my hand before I bought it. I just don't know about purchasing used lenses from the internet. I know people who have and it's been mostly good results for them. But the one or two horror stories still scare me from doing so myself.

I know that whichever you choose will open a new world for you and I'm excited for you. I remember my first DSLR and it was a truly life changing event.