As my first TF project, I'm building a small shed (12X8) in my backyard for storage and would appreciate a little help. I live in Toronto, so we don't see a lot of timber framing around here!

1) What size timbers should I be using for this size shed?

2) Can I just float the floor on patio stones on each corner and under each post?

3) What kind of time commitment will it take to prepare the timbers?

Thanks in advance!