Hello, I have an HP photosmart C6280 All-in-one, works great with the usb connection and I also managed to connect with ease using ethernet connection with the HPLIP installed and you also need the HPLIP-GUI installed. Have your printer on and then go to SYSTEM/PREFERENCE/HPLIP TOOLBOX, it will say can't find printer (or something like that) but there is a button to click on for it to look for a wireless/wired connection, shouldn't take more than a few seconds, and it will find your printer, and off you go.
Don't buy a Kodak brand printer, while linux can see my Kodak printer with any connection ( USB, ethernet, or wireless) there are no drivers avialable.