The simple answer is that every group is different so it's best to find out the policies of the group you plan to foster for....the group I volunteer with does take the responsibility of placing the kittens. We cover the cost of food/litter/medical until the time they can be placed. We also spay/neuter all the kittens before they go into homes (which helps to ensure they will not become accidentally pregnant) as well as spay the mom.
What you may want to do initially is get involved in a voluntary manner (I started with this group simply being a dog handler at adoption events) before considering fostering. Many groups hold off site adoption events and can always use volunteers to play with the cats or walk the dogs.
I agree...it is far healthier for any cat that isn't involved in a breeding program to be spayed.
Katie
