A more important piece of information for a first time fish tank owner is to get his head around cycling the tank. That is a process you should start right away before even worrying about what fish to get. That way, when you have everything figured out, you will only have to wait a shorter time before adding in your first fish. There is a link to fishless cycling and to fish-in cycling in my signature area. Once you have read through the information there, you will probably have lots of questions on how to go about doing your own cycle. Please feel free to come back and ask for advice on that subject, it can be a bit hard to really grasp at first.
As far as selecting fish, I find it is often a question of tastes when it comes to a stocking plan. I would suggest that you wander the aisles of your local fish shop and keep in mind that many of the fish on display grow much larger than they look in the store. Just write down things that appeal to you and that are small enough for your new tank. We can help you put together a stocking list from the fish that you like. Be aware that different fish require different waters so depending on how hard your water is, we may suggest an alternative that looks somewhat like the ones that you liked has a similar appearance.