If you have ammonia, then the tank isn't fully cycled. You should be checking your levels every couple of days during the cycle. That way, you can see your ammonia go up, then down. As your ammonia is going down, you will see your nitrite go up. Then your nitrites will start to go down, and your nitrates will start shooting up. When the nitrites have dropped back to 0, do a massive (like 40-50%) water change. Check your levels a day or two later. If ammonia and nitrite are 0, and your nitrates are substantially reduced from the pre-massive-water-change level, then you are cycled. DO NOT add any critters prior to completing the cycle, no matter what your LFS says. It's cruel and will actually prolong the cycle, not speed it up.
Just another thought, but you reeeeeeeaaalllly want to avoid damsels as a first fish. They are very territorial and aggressive, and will attack and kill fish much larger than they are. They end up causing many headaches. Clowns can also be territorial, and you don't want more than a pair of them. Start looking at what fish you want to keep. Keep in mind that you will be limited to 7-8 fish, and consider the tank size requirements of the fish you are wanting to get. Remember that even if a fish is a juvenile, it still needs to be housed in a tank roughly the size it will need as an adult. Check out
LiveAquaria for ideas. They are pretty good for research, and they list minimum tank requirements, adult size, temperament, reef-compatibility (if you're considering keeping corals) and many other pertinent details you will need to consider when stocking your tank. You mostly want to add fish starting with the most peaceful one you're wanting to keep first, and progressing to the more aggressive fish. The more aggressive the fish, the more likely it is to pick on fish added after it. Thus avoiding damsels as the first inhabitants of the tank! Good luck!
