Do you mean where to *buy* tie dyed prefolds or how to make them?
You can buy a kit at Wal-Mart or JoAnn that includes three colors of dye, squirt bottles, soda ash, etc...it has everything - for like $9.99.
This is the best kind - DON'T use Rit - it sucks.
There are great directions in the package on how to dye and get different patterns.
It says it dyes 8 garments, but I was able to dye around 20 - since they were small. I'd say you can easily do 2 dozen CPFs, maybe even 3 (there are directions on watering down the dye to get pastels in the package).
As for the snappi'd prefold - we do them all the time at home. DD has been able to unsnappi one side before, but that was only once. For the most part she leaves them alone.
They do get wet on the outside, so if you don't want damp spots on the furniture, get a wool cover for around the house. We just let her go coverless and change her as soon as she pees in it.
That way we REALLY know when she pees! :LOL