Besides, it's too small to put my hard drive and iPod.
1 - Any stock pieces no more that 6" x 18" IKEA draw front are ideal.
Lots avail in the as-in bins.
2 - L brackets
3 - Zip saw & belt sander
Another notch if you need to run cables
Use belt sander to bevel all edges, else the shelf will not be level
Screw on the shelf edge, but not too tightly.
If all is well, shelf & bracket should be flush.