If you are in the market for a digital camera, you should check out
http://www.dpreview.com/ since it has reviews on almost every digital camera on the market.
Most cameras I've seen have very small optical zooms. I think the largest optical I've seen on a non-professional digital camera was on an Olympus and it had 10 or 12x optical zoom. Nice camera, but a little higher than your price range (I think its $700 or so).
There are a couple of options for storage. There are Compact Flash cards, Sony Memory Sticks, SD cards, XD cards and floppy. The difference between them is the speed of data access and storage. XD cards store and retrieve data faster than compact flash in my experience, but usually cost a little more too.
Anyway, enough of my rambling. Check out the above site and you should be able to find the perfect camera for your needs. Good luck!