Well with the tank predrilled you will need a sump and a return pump or two. For that size tank you could do two return pumps with 1 going to each return.
What size pump will really depend on how much flow you want and how many feet the sump will be below the tank. For submersible pumps look at the Mag drive product line. Maybe a pair of mag 12.5's
For the sump it does not have to be anything extravagant. For a tank that size I would suggest maybe a 40-50gal capacity sump. Now you wont end up running the sump at full capacicity as you will want the water level low enough to provide for if water flows back down the overflow and return lines when power cuts off.
For the two return lines you could get one way flap valves that will help prevent backflow of water from the returns.
A skimmer is something that would be of benifit to you.(in the sump)
A pair of 300W heaters would be good (place them in the sump)
Lighting. if your doing FOWLR
then you wont need HIGH output lights but you will probably be happer with lighting that is brighter than your standard florecent tubes.
Maybe go with 6 110W VHO
bulbs or maybe a half dozen 96W PC
How long is the tank? A pair of MH
bulbs with VHO
actinic would look really sweet and if you put 250W MH
bulbs you would be set for most corals if/when you go that route.
Other things you would need as far as equipoment would be test kits, hydromoter, and themoter.