Most people who have decided to get a fish tank are very excited about the prospect of starting as soon as possible. I was impatient too! Try not to succumb to this, however. A newly setup tank is a very sterile and unbalanced environment for fish (even after the dechloronating water conditioner is added).
This is because beneficial bacteria have not established themselves in the filter yet, and fish waste will just accumulate as toxic ammonia and have nowhere to go but back in the fish, which can poison or stress them to the point of disease (stress = suppression of the immune system). Once established, the bacteria in the filter will convert ammonia to steadily less toxic forms (nitrite and then nitrate), but this takes time and is not going to happen overnight.
For this reason, it is not a good idea to stock your tank all at once--this can lead to a common mistake beginners make called "new tank syndrome". Please read the articles linked on the right for more information on "cycling", and how taking the time to do this can save your pets lives later. Once established, a balanced tank can be relatively low-maintenance, just requiring regular feedings and water changes (very important).
My other articles to come in this series will outline ideas and suggestions to take as you build up your tank home and make it a healthy and happy place for your finned friends to live in. As you gain confidence in this hobby, you may want to try more advanced setups, such as creating a planted aquarium or starting your first marine tank. Hopefully it will be a fun process that you will enjoy sharing with others, as I enjoy sharing this with you.