That's about right Ian.
Crossings:
I've only used 2 companies in the past, Norfolkline were my prefered crossing. They're cheap, normally paid circa £40 return, it's a 2hr crossing but it gives you a chance to have a decent (albeit overpriced) breakfast and a sleep if it's an early crossing. It also takes you 30mins further down the French coastline so reduces your driving time. Eurotunnel are fast and reliable but you pay a premium for this.
Fuel: I filled my tank up in Harlow (Essex) and made it Nurburg on one tank (380 miles) which was impressive in my Impreza, normally budget a tank and a half.
Accommodation: €50 per person per night for a decent hotel, guesthouses cheaper.
Lap prices for 2009:
1 - €22
4 - €75
8 - €145
15 - €250
25 - €390
JK - €1075
Food and drink: €50 per night for a nice meal and drinks.
Hope this helps.