The easy part is finding lengths of PVC pipe in a variety of diameters. Schedule 40 PVC pipe is the most common in home improvement stores. Furniture grade PVC is harder to find a bit more pricey.
The hardest part I find is finding the right fittings for your projects. Most hardware stores will carry the basics like Elbows & 3-way tees. Unfortunately, the most used fitting we use in our jumps & weave poles, the 4-way tee, is not carried in stores. I have searched the web for the cheapest seller of these hard to find fittings.
And then I found Formufit. They offer all those hard to find fittings as well as Free PVC Plans for a few agility items.
You can purchase fittings on their