Building a pedal board has been done many times. I wanted to build something that looked nicer than most of the DIY ones I have seen, took under an hour to build (not counting finish) and was under $20. I think I met all the goals.
Step 1: Step One: the Materials and Cut List
From that piece cut the following:
Top: 11.5" X 17"
Sides and front: 2" X 24" (these will get mitered to fit around the top)
back and stiffening strips: 3/4" x24" (the back will get mitered as well and the stiffeners cut to length after everything else is assembled)
Step 2: Profiling the Edge Boards to Make Feet.
I used a 1" forstner bit to make the curved corners then cut out the waste with a jig saw.
Step 3: Add the Sides, Front and Back
I used yellow wood glue and 18ga. air nailer to attache the surround to the top. If you don't have an air nailer, you could use 6 penny finish nails and a hammer.
Step 4: Sand and Layout for the Wiring Slots
Layout the 1" wide slots 2" in from either side. They are spaced 2.75" down from the top and up from the bottom then two inches in between them to give 3 slots.
Drill the ends of the slots with a 1" bit then cut the straight lines with a jig saw.
Step 5: Finish Assembling!
Adding a finish is up to you. I haven't decided between vinyl, carpet or just spray truck bed liner yet.
I will do another instructable on how to make jumper cables and mount everything.