I bought two maps of Le Mans from Stanfords book shop in London.  The first produced by Institut Geographique National (red cover) does not go far enough north to show the motorways and cuts off half the circuit.  Before my second trip to Le Mans I found the Blay Foldex version (yellow and orange cover) which being two sided provides much better coverage and enables you to find your way from the motorways to the north and goes all the way down to Mulsanne.  Both have maps of the centre of town if you need one.  I think both cost less than £5 each.

Will I need a parking permit for the practice/qualifying days in June?

The booking form says "Parking outside the circuit are free of access on the practice days (except the numbered one)"

Can someone provide a translation?

If this means I can get into the Blue car park (but not White or Red) for free what's to stop me staying there until the end of the race?