From England by ferry
There are numerous crossings available into Calais (north France), and for here in Normandy there is Brittany Ferries who offer Poole or Portsmouth to Cherbourg and Portsmouth to Caen (Ouistreham.) There are additional services to Dieppe and Le Havre etc. Here is a good travel guide detailing the different ferry routes to France
Basic French facts
The time in France is CEST (GMT+1) and the Currency used is the Euro - there is a currency converter on this page. You can change money at La Poste (Post Office), but the best way is simply to draw out cash from the ATM machines, of which there are several in towns like Bayeux and Carentan, the exchange rate and fees are normally as low as you can find. You will need to know your 4-digit pin code of course! Definitely don't come armed with 100$ US bills, banks in France often refuse to change them - bring nothing larger than 50$ bills.