Alright, a tube is the least of your worries (but should be on the list). These things are very easy to make. Get a 5 gallon bucket for each plant you plan on growing. Buy netpots at the hydro store along with the hydroton and nutes, at walmart they have a "Tetra" air pump system that says it will take care of 20-60 gallons ($20). I'm using one pump for 2 plants and it's working like a charm. You will need tubing which is right next to the pumps ($2 for more than you will need), airstones (2 for $3.50). You will have to clean and replace them eventually. I'd get 3 for each bucket.
Then you just need to poke a hole the size of the tubing in the upper area of the bucket. Run tubing through, weigh airstones down, put in water and you're set. You may want to pick up some water conditioner while you are at Walmart. It comes with a little cup on the top (kind of like nyquil). It is so you can remove harmful chlorine from tap water. If you don't want to spend that $5 (will treat ALOT of refills), let all water sit for one day before letting it touch the roots.
This is a very basic setup, and frankly I think it's the easiest part of the whole process of building a grow system. That being said, if you can afford it go with the premade system. I'm a lazy ass too, and when I can afford it I usually pay extra for things like this. But since I was buying the whole setup at once I decided to make some homemade DWC buckets.
But if you have a drill and a Walmart nearby you can do this very easily.