Give it a little more time ... if she isn't finished delivering yet, then it is possible her milk hasn't come down. Allow her to eat the placentas as this will stimulate the milk to flow. She will move the babies into proper nursing position when she has completed delivery and can focus her attention on feeding.
I agree with Gaye. Remember to *breathe* and try and be calm. You will know if she is not producing milk if, after things have settled after the birth, the kittens aren't attached to a nipple and seem sqirmy and are crying. Keep us updated and we can let you know what to do if she really isn't producing any milk.
I get so worried and excited about these things. She delivered 3 beautiful kittens last night, and seems to be producing milk well now. She's still a little sick, but just more stuff up than anything. She's purring and happy