still haven't found anything 'proper' but sent this
umm ......
http://cats.about.com/cs/kittencare/a/findkithomes.htm4. Keep the kittens for at least 8 weeks. If you remove them from their mother before then, the kittens will not have completed their "basic training." Even at 12 weeks, although much more autonomous, the kittens are still establishing social skills learned from their litter mates and mother.
http://www.breedlist.com/faq/young.html"Kittens should leave their homes at a minimum age of twelve weeks," says Dr. Betsy Arnold, DVM, a veteran Siamese breeder and veterinarian with an all-feline practice in Rochester, New York called Caring for Cats. "In my practice I have seen kittens coming in at six and seven weeks who weight twelve, maybe fourteen ounces. These are infants. They needed to stay with their mothers."
Twelve weeks may seem old to people accustomed to seeing newspaper ads advertising kittens who are "ready to go" at six or eight weeks of age. Most of us who have had cats have acquired kittens that young. They are cute at that age, and most people enjoy having such young kittens to watch them grow. However, we may permanently harm kittens by separating them from their mothers so early. There are crucial mental, emotional, and developmental milestones that a kitten experiences between six and twelve weeks of age. Separating the kitten from mother, siblings, and familiar surroundings at that age can cause undue anxiety and stress at the least, and serious medical problems or even death in the very worst cases.
what sites did you look at?