there are a few places on the net that do it commercially, its fairly expencive but if you're serious about it, and want to sell them (as art prints), thats how to go about it.
For small scale sheets, use number 14 watercolour paper, and screenprint or stamp you're designs onto it, then perforate with a perforator wheel (you can get them on amazon)
If you make you're own, test the inks you use to see if they are soluble in water and alcohol, as if they are they will run when (if) impregnated