Gary,
Yeah, what Wedge said. I just wire the pvc extensions to the t-posts and use the cheap flagging tape that's used to mark stuff. The yellow is the cheapest, and when you wrap it around the pvc it clings pretty well. It blows in the slightest breeze and makes weird noises which may help scare off the deer. I was once working in the garden on a windy day and the humming that tape made set my teeth on edge. Cheap nylon cord works fine, too, but I figure you need to flag it with something so the deer can see it. I used the same roll of cord for about three years and hung plastic grocery sacks on it. No deer in the garden either way so far.
I don't seem to have nearly as many deer roaming around here lately. I don't yet have my fence up and I've been using Liquid Fence on the beans and anything else I think they might munch on until I do get the final tilling done and get the fence up. So far no damage from deer or rabbits, and I have seen as many as three rabbits running around at one time. Of course, you don't want to spray that rotten egg stuff on anything you're gonna harvest any time soon!
Chuck