First off, Welcome to marine aquarium keeping! Doing the math, your tank is a little over 25 gallons. As far as marine aquariums go, thats a fairly small tank. Not micro, and not biocube, but definitely on the small side. Small isn't bad necessarily, but can require more work than a larger tank.
Second, I cannot agree more with bnr911. The more you know beforehand, the better off you are later on down the road. Always do your research before making a decision. Someone else's experiences can save your tank!
Now, to start off with equipment. You are going to need 3 basic, but crucial, pieces of equipment. One is a filter. Duh. Depending on how you set your tank up, it could be anywhere from a basic HOB, to a more complex sump. But that's for later. The second piece is a protein skimmer. It helps, especially in a tank with corals, to keep unwanted "stuff" out of your tank water. The last piece, or pieces, are powerheads. They help keep your tank flowing, and with corals, keep nutrients at hand. Now, to put this all together, you have a few options. I don't know how much space you have underneath your tank, but if you have a lot space, a sump or refugium it a great idea. A sump is basically a HOB, but bigger and better. It takes care of everything a HOB does, and gives you more gallonage, and space to hang other pieces of equipment, such as a protein skimmer. If perchance don't feel the appeal of this idea, then you could do a refugium. The idea is to put a smaller tank beneath your main tank, flow water into it, filter it, then pump it back up to the main tank. It hides all the equipment, adds gallonage, and you can put plants, such as mangrove shoots, in it to add filtration. They are both similar, but a sump is a working filter, whereas a refugium is an extra tank. If you don't/can't do either of these, you can just hang the equipment on the main tank. This takes away from the look of the display tank, though.
As a last note, stock. I understand you haven't decided what you want in your tank. You have to remember this ALWAYS when you stock: there's what you can do, and what you should do. Sure you could house a yellow tang, but should you? Not really. And lastly, corals are part of the stock as well. They eat, and thus produce waste. If you stock your tank, not planning for your coral's bioload, you're asking for trouble. A great website for planning fish stock is aqadvisor.com It is a great website for begginners to see what their stock actually looks like.
Have fun, and remember, the only bad question is a question not asked!