I asked my brother, who is in the British Army and has taken some tours of the battlefields, for some advice, and he suggested maybe looking at the British tour company, Holts (http://www.holts.co.uk/). However, their tours may be a little long and structured, plus are confined to certain dates. Another option might be Viatour, which aggregates local tours and offers a couple of Normandy WWII outings here: http://www.viator.com/normandy-tours/d183-ttd?pref=02&aid=g1285. These include a two-day trip that leaves from Paris and a daylong private tour from Bayreux (sounds like they customize based on interests, accessibility, etc.). Lastly, a Web search will throw up any number of tour options. This guy looks to offer a pretty interesting set of itineraries: http://www.ddayhistorian.com/, plus comes quite highly recommended.