If you really plan on getting into photography for the long term I would recomend a DSLR, a nice entry level model close to your price range would be the Nikon D50, with an 18-55 kit lens it retails for $699, but I've seen it in a few places for $599. It can be used in fully automatic programed modes and you can wean yourself to fully manual operation or any combination in between. The 2 largest immediate problems are the steep learning curve, and the kit lens (18-55) gives you no macro ability and very limited zoom capabilities. The latter can be easily resolved with additional lenses, however this obviously adds to the cost of the camera.
The other option is a point and shoot variety camera. I've been a big fan of the Fuji Finepix S9000, you can find it for about $450 these days and it has a 10x optical zoom and a killer macro. The chip is kinda noisy (but I'm picky) but then again so are most point and shoots. It is a camera you can grow with and it makes excellent images. I haven't researched point and shoot cameras in some time and I know my S9000 recomendation may be kind of dated as there are a whole fleet of these cameras these days that will make excellent images. The big thing to look for is optical zoom (not digital) and closest focus (macro), all things being equal the next feature I look for is ISO range.
If you have any specific questions, or hone your choice down to a couple of models or feature sets PM me.
