Hi Cindy, I got the PRS-505. I did a lot of research and thought that it was the best bang for the buck.
It doesn't have the wireless capability like the kindle but they are coming out with one. Personally I didn't really care about the wireless. The wireless provides the ability to download without having to plug into a computer. The Sony reader came with the data cable and it worked great transferring from my computer to the reader and it also charges when you plug it in.
I also purchased an AC charger for short money just in case I need to recharge while away from my puter.
The resolution is real easy on the eyes and I do love that I can make the print bigger. Sometimes at night I can't put the darn thing down and I need the bigger print because my eyes are half shut.
You can take a look at the sony store
http://ebookstore.sony.com/.. gives you an idea on how their prices are and such...
plus you can order books through other service as well like ebooks.com
I don't think you can go wrong with either the Kindle or Sony. I heard that borders is coming out with one as well.
Hope this helps.. Feel free to ask if you have any questions.. Ill answer as best I can.