McMaster-Carr is definitely the place to shop!
http://www.mcmaster.com/
Try searching on 'threaded rod'. Click the first link found. You can then refine the search by clicking on the various attributes. I used 'english', '3/4" #10', 'zinc-plated steel'.
For nuts, search on 'hex nut'.
For washers, use 'flat washers'.
They have an incredible selection, fast delivery, and better prices than anywhere else I could find in my area.
I cut my rods with a hack saw. Took a little work but it wasn't bad. Be sure to thread a nut on before you cut. Then take the nut off and it will help remove burrs from the threads.