One thing about Top flight is you don't have to go straight to giant scale - they have some great 60 size planes too.
BTW, my last building board consisted of a 2x4 piece of 3/4 inch cabinet material and a 4x8 sheet of pink foam wall insulation from Home Depot. I had them cut the 2x4 (24x48) into 1ea 8x48 piece and 1ea 16x48 piece. I cut the insulation to fit on top of each piece. The insulation had a sticky back so it stuck to the boards. And get some T-pins from the hobby store or Tower. I think you can see the building board in My Gallery under the Stampe photos that are dark and orangish in color.