This can be done painlessly if you have a little bit of woodshop experience under your belt. Go to HD or Lowes and buy some 10" Select pine boards and 2 or 3 8' flourescent fixtures.
(They have nice oak boards there too but they are obviously a lot more $$$)
Build a simple box and use some 1/4" plywood for the top. Mount the fixtures to the plywood top. You can buy the 2'x4' chrome diffusers there too or order directly from Diamond. Then you can add some nice decorative trim pieces around the edges, stain and varnish and you're all set.
There's a lot of folks on here that have done this sort of thing, I'm sure there will be many examples to follow...
Snipershot made himself a nice home-made light that also doubles as a tanning bed/plant grower.