[KurtG]

I use either a miter box and hand saw or a straight strip of wood and a couple of clamps and my circular saw to get a straight cut (I am looking to get a table saw soon).

With the wood strip and clamps, you just have to measure the offset of the blade to the line where you want to cut to use the wood to guide the saw. I use a straight 6 or 8' piece of 1x2. It may take a little fiddling at first until to get the correct distance to clamp the wood. This method is good for ripping ply.

The miter box works good for cuts on the type of 1"x3" stock you are talking about.

I built my stand and canopy with this method.