MaxiJets are good, inexpensive, and reliable power heads. They have very narrow flow, though. They would work fine for your tank, IMO, for just getting going. As mentioned, they can work on a wavemaker (work very nicely this way), and can be modified to produce wider (and more) flow.
Seio pumps (M820s) are also inexpensive. Some find them to have restart problems when they are switched off. I never had any problems with mine. They produce wider flow, and are very good powerheads, IMO. A couple of these on opposite ends of the tank can produce some nice flow patterns.
Tunze Streams are _expensive_ but reliable, and can operate at multiple output levels. They produce very wide and soft flow. Very nice. Since you are just getting started, I would not recommend these. I recommend getting some experience under your belt first. Then you can make a more informed decision based on your own needs. These are what I run in my 90 gal.
Tunze Nanostreams and Hydor Koralias are smaller, lower cost "wide-flow" powerheads. They are also very new and are still working out the kinks of being brand new products. I recommend steering clear of these until they have been on the market for a year and have the kinks worked out.
For your 72 bow my first recommendation is the Seios M820s, followed by the MaxiJets.
