Building my own shelves.? I'm building shelves in my room and need to know how wide-ranging...

I'm building shelves in my room and need to know how wide-ranging (thick) the average piece of wood is, I'm buying from Home Depot. I'm guessing that they're about an inch thick, but if anyone have a more exact measurement, that would be great,
If a picture paints a thousand words, after...
Answers:    My dad is making some cubicles, and the wood is 3/4 inches thick. he built a canoe, on his own, no tools, so I'd go with that. :]
How much will it cost to dress up...
Most shelving objects will be 3/4" thick.