This topic has come up in at least 14 different threads. Search on "print on fabric". Go through all of them because each contains little snippets of valuable tips. You'll also find a few links to articles about using "The Stuff".
"The Stuff" we're talking about is Bubble Jet Set 2000. Made by C. Jenkins.Easy to use. Works great if you follow the directions.
Recommended for use only on 100% natural fibres. When printing on cotton, a 200-count or higher weave is consistently recommended by those with the most experience.
Best results are achieved when you use a printer with dye based ink. Canon and Epson keep coming up as the top two brands for best results. I've found from experience that the older HP inkjets gave better results than the newer models using the fancier ink. (Go figure. LOL)
There are a lot of places to buy BJS. I get mine from Dharma Trading Co. Their prices are consistently lower than any others I've found. (The exeption is at Joann's when you can use one of their famous 50% off coupons, or if you stumble across an unusually good sale somewhere else.)
The companion product, Bubble Jet Rinse, is relatively expensive. Any super-mild detergent will do. Woolite is often recommended, as is Synthropol.
Happy Printing :-)