To cut the plywood into circles, as well as cut the support pieces to length will require a jig saw and wood blade.
The outside diameter of 2" schedule 40 PVC pipe is 2.375". You will need a drill and a 2 3/8" hole saw to cut the holes that the pipes fit into.
You will also need sandpaper to smooth things out and maybe to enlarge the 2 3/8" holes slightly to get just the right fit for the tubes. 80 grit will work well here.
A screwdriver will be needed to mount the supports on to the circular wood pieces, and a small drill bit with the drill you bought will pre-drill the screw holes. Size of drill bit depends on the shank size of the screws you use.
For the PVC pipes:
You will need a way to cut the pipes and the flanges. A PVC hand saw would work well for this.
More of that 80 grit sandpaper will work for smoothing the rough edges of your cut pipes.
Mr. Havlena used a hot glue gun to secure the PVC tubes into the wood.
You will need PVC primer and glue to attach the PVC supports/flanges to the pipes up on top, as well as to connect the pipes and elbows together.
Lastly, a small hammer is always useful for fitting parts together that need a little persuasion.