I checked it out. The main thing I was looking for was a supplier, like someone who can provide wholesale cost for bulk orders.
The website link you posted at the bottom will get you to a printer, but their prices are pretty steep at face value. There is an option to inquire regarding quotes for larger orders. I will wait to see what I hear back, but basically if you are designing per piece then you will pay approximately $23-$25 AUD Australian Dollars (which is about $18 USD) and that makes it hard to resell at retail because of slim margins. The average retail t-shirt in the U.S. is about $25 USD so and $8.00 margin before shipping costs is to rough to romp on. Thanks for posting this though!