I went in 2003 with a few friends. We took the bikes from Portsmouth to Caen on Britney Ferries, the ferry was (imo) expensive at £121 but since it was an overnight crossing I had to book a cabin - they wouldn't let me not book one.
The route from Calais was about 300 miles, we took the scenic route but I couldn't begin to explain what that was! One of the guys with us knew where he was taking us... I just followed and enjoyed!
We stayed in a small family run hotel in Nevers called Hôtel de Verdun -
hotel.de.verdun@wanadoo.fr - they spoke good english (and found humour in my efforts to communicate in french!), the rooms were good and the brekkie was quite substantial for a french effort. Only thing was the bikes had to be parked on the street out front, but there were concrete posts to chain them too.
As said, Nevers is about 10 miles from the circuit and easy enough to find. The town has plenty in the way of eating/drinking facilities and everywhere was very welcoming. Not much in the way of entertainment if that's what you want.
As for the race meet... it was great! Didn't cost much - i think it was about £55 for tickets which included Saturday/sunday circuit entry and also paddock access. We didn't pay for the main grandstand but there were better viewing spots elsewhere around the track. Although we managed to blag our way into the grandstand for Saturday qualifying cos the guy wasn't such a jobsworth as they tend to be over here.
Finally...
yes, it was worth it.
(edited: just found the ferry info!)