i suggest you go with melamine. a sheet is about 20 or 30 dollars but would provide you with plenty to build your rack.
heat tape... id get the 3 or 4 inch flexwatt and you can find that at
Bean Farm at a good price.
youll need a table saw (or something that will cut through melamine in a strait line) and a drill and some screws.
i highly suggest you wire the flexwatt to a dimmer or thermostat. i seen thermostats selling for like 20 bucks on here somewhere... mine is wired to a dimmer switch in a side mounting gang box. youll need wire nuts as well.
as far as tubs (sterilite or rubbermaid 6 qt. shoeboxes) you can find these at walmart, k-mart, target, longs ect...
cut the melamine, measure the heigth of the shoebox, cut an additional two pieces of scrap melamine to that heigth (youll use these to make sure your shelves are uniform), assemble rack using melamine scrap pieces, screws and drill. theres your rack.
wire the flexwatt. you can get instuctions on
Clay Davenport's Website .
drill holes in the shoeboxes and you're done.