Caroline,

You need the plug and a transformer adaptor. The adaptor will step down the electricity to American standards. Here is a photo of the plugs: http://www.glasson.com/nfo/electricity.htm

You plug the three-prong plug into the socket, the transformer into that and then your appliance into that. Don't take a hair dryer. They will be available in all your lodings. When in your room look in the drawer, closet, etc. and you will find one tucked away for your use. If there is not one in your room, your hosts will loan you one. American hair dryers do not do well even with the adaptors. You could blow a fuse at your lodgings or set the hair dryer on fire. Use the one at your B&Bs.

It sounds like you may already have what you need but without seeing them in person I can't tell. Here are photos of the converters: http://www.franzus.com/page/FOS/CTGY/ELEC-CONV

Michele