J.H.
I will be anxious to see the replies-as we're having the same issue! My 12-month old will soon need to go to daycare. However, he cries the whole time at the church nursery, and that's barely an hour! He's also very clingy to me and shows a lot of stranger anxiety. Between 5-7 mos., he had a babysitter 3 days while I worked, and he LOVED her. No problems at all; unfortunately she moved. Then I had him at a home daycare/preschool with his sister, and he was miserable. Didn't eat, sleep, cried, etc.
Without going into the whole story, now we're going to have to have him in daycare again and I can't imagine that it will go well-we can't afford a babysitter, so it will have to be home daycare or a center. I've never gone through this before as my daughter was the complete opposite-she's adjusted instantly to both places she's been and is very social. I guess it's about temperament. Sorry not to be able to offer any advice; just wanted you to know you're not alone.