As I mentioned before, we combined a family holiday with LM this year. In the past, as the kids grew up, we had some great holidays in France so it was a good opportunity for us all (11 of us). We often used Eurocamp either in a tent or a mobile home, we always found the sites good, clean and with great facilities. So given that Brads little ones are are 3 and 10 months and their cousins are 3 and 4 we needed a good family site, not far from a port and ideally on route to LM. So last October I reserved 3 mobile homes on this site
http://www.eurocamp.co.uk/campsites/normandy/nr011-chateau-lez-eaux/ataglance.html with ferries on the Portsmouth Cean route, out on the 6th and back on the 18th. This meant Brad and I could head out to LM on Thursday, have a nice quiet and relaxed race weekend, know that Caroline and the boys were sorted so we could return on Sunday. It worked well, the site was great , it was less than 2 hours from the port and about the same to the track.
Given the Euro football next year it may be worth looking at as they will have a pre allocation of ferry crossings at a better price, bookings will start in October.