Goldfish are extremely messy fish and require a LOT of water. They also get quite large, you could maybe do 2 of the fancy variety in a 29 gallon, but have nothing else.
There is a sticky on the top of the forum here that talks about the cycle new tanks go through, here is the link: http://www.tropicalfishkeeping.com/f...m-cycle-38617/
In short, it takes 2-8 weeks (usually at least 4) to complete.
Until the bacteria is establish, you have to do partial water changes. Have you been changing the water at all? Recommended is at least 25% once a week, but up to 50% each week. You'll have to do it more often (daily) while the tank is cycling to keep the Ammonia, and later Nitrite's down so as not to kill the fish.
A 'fishless' cycle is a far better route to take, I would see if you can return the gold fish if possible and pursue that method.
Using chemicals can be more harmful than good and can even extend the length of the cycle, and you have to be careful. The ones that get ride of Ammonia often just change it to a different form of Ammonia that isn't harmful (but still shows up when you test the water).
So if you can't return the fish... keep up on water changes, don't use any chemicals to 'help' it along, and consider getting a liquid test kit (for example API Master Test Kit) so you can monitor the progress of the cycle. Once it is finished, you'll have to decide what to do with the goldfish, because with three of them you really can't put anything else in the tank (plus they prefer colder water than most tropical fish will tolerate).