Diane - I got one answer! The pipes are mostly 3/4" but a few are 1/2". He can't remember the name of the tool that he used for cutting the copper. He has more of them to do tomorrow. Maybe he'll recall the name when he's using the tool or else I'll just take a photo of it.
Debra - I did see some very pretty pointed ones but resisted the urge to buy them.
Wine stoppers were the ideal answer to decorate this "fence" that once was our asparagus fence but then I moved them to a bigger plot along with new asparagus. Beware! They faded and lost all color.
