Agree with Watson and chuckcac . . . there's three secrets to a successful saltwater aquarium: research, more research, and even more research. Get a book or two (Fenner's THE CONSCIENTIOUS MARINE AQUARIST it top-notch, and there are others), spend a lot of time on this board, and thoroughly think the process through. Just picking out compatable specimens is time-consuming and an artform unto itself.
Actually I lied, there's six secrets to a successful saltwater aquarium . . . the other three are patience, patience, and even more patience on top of that. This is a slow moving process and a vast majority of problems people experience can be attributed to (intentionally or unintentionally) rushing. Wouldn't surprise me if you're two or more months out from completing the purchase of your hardware (Tank, filters, etc), and probably another month or two after that before you see fishies swimming. Believe me, the wait is worth it. My wife and I spent a good couple of months just doing research once we decided to take the plunge, and we're glad we did as our (Still fairly new) experience has overall be very good . . . thanks in no small part to our own research and what we learned here.
A few other tidbits of advice . . .
-- Go with the largest tank you can afford and/or accomodate space-wise. A larger tank tends to keep water conditions more stable, and your options with livestock increase tremendously with a larger tank. If you want a tang, most people here will advocate a 5 or 6 foot long tank around 120g, more even better.
-- While it doesn't have to break the bank, this is an expensive hobby and I believe it has a strong "you get what you pay for" element. Judicious shopping can keep costs down, but pay a bit extra to get quality, durable components . . . you'll save money, time, and effort in the long run.
-- It can vary, but local fish stores in general have a bad reputation (Which you'll quickly see as you read threads) of offering bad advice, be it for equipment, treatments, approaches, and livestock. Know-before-you-go (to the store) so you can make your own judgements on what a LFS is telling you. Remember, they want your money and probably consider themselves vastly more educated than their customers, so they can pass off any failures/problems even they themselves caused to the inexperience of the customer.
And welcome, this is a great board.
