Garages will be first come first served. As long as you're in before about 8am, you'll get one, and everyone just piles in anyway
Also, you can't get in to the circuit the night before, so you'll either have to park outside if you're coming up Monday night (I know its a trek for you too) or find a B&B or layby.
I'm sure you'll pick up the track in no time, and we'll probably all end up chatting about it a whole lot anyway.
It's loverly