PP, I haven't read the other replies, Im lazy LOL.

I didn't start Evan in care till he was 3. I felt it was more a "preschool" then simply child care.
What I did with him & any good center should let you do the same is to come in & stay with her for a an hour or so & then you BOTH go home. I did this almost every day if not every other day for about a month before I actually left Evan. This gave him plenty of time to get use to the carers', the new environment, toys, kids etc.
We got a few tears the first few times I left but it didn't last. I trusted their word that this was the case as I would call before i left the area, so I would walk over to the shops & get bread etc if I needed too & before heading home ( I would walk) I called & I know I would have been able to hear him if he was still upset.
What I did find happen though was after about 4 weeks of 1 day a week in care he became more clingy at home. I couldn't go to the toilet with out him in a panic of whre I was. I spoke with the preschool & they said he was coping fine there. But I still thought about pulling him out seems it was at home he had troubles. But we stuck with it & it got better pretty quick.

So If you can I would maybe ask if you can still come in 2 or so days a week to help her get use to it all. Go in for morning tea then leave after an hour or so. They should not charge you for this. YOU are still looking after her & she is still your responsibilty while you are there.
Personally for me if they don't encourage you do do this then find somewhere else to take her.

BUT when you do leave her, don't hang about, Drop her off let her know you will be back, a kiss, good bye & walk away. then maybe come back after lunch rather then a full day the first few times so she knows you will be back.

But also at the end of the day if you feel she isn't ready & you don't need her to be there then keep her home. I was told kids don't need or seek out social interaction with kids their age untill about 3. Before that they are quite happy with Mum & dad as long as they are playing games & providing that fun & stimualtion. Play group, Outing etc. At this age kids are all about themself. So if you don't need it then keep her with you.