A standard 1" black plastic tubing is commonly used, matter of fact that is what most wells use between the well pump and the house. You can get that stuff in the plumbing section of any home depot or lowes. It's not terribly expensive for a 100' roll.
One suggestion I would make to you is if you're going to do this help yourself out and make the system
easy to break down or put together. I just ordered some cam locks a few male/female pairs with plugs (for winter time) so when I assemble or disassemble my water lines I'm not screwing stuff together, messing with clamps, or otherwise needing tools. These things are awesome, female on one end of a break, male on the other. They just lock the levers in place and pin insert lock pin, instant water tight connection. Easy and hassle free. Well worth the investment. I swore when I took my water system apart this past fall I would fix it so it wasn't such a pain in the neck next time. They are inexpensive and well worth the money, here's where I got mine..
http://www.globalindustrial.com/g/pl...mlock-fittings
Best thing I ever bought can't wait to fix my system for good.