Recommended 767 tools.

Freeware Fuel Planner (two choices, depending if you have NET.framework installed or not) :
http://www.nofuel.thatssailing.com/flightsimulator/fuelplannerb763/default.asp

Freeware De-rated Takeoff Calculator DTOCalc: http://mbev.net/lds767/ldsflyingclub/DTOCalc.zip

I also use the LROPS guide, which costs a little money, but is worth it in my opinion for realistic transatlantic flights.  You can read my review of it on AVSIM if you want: http://www.avsim.com/pages/0809/Book/LROPS.htm