I like parenting books by Sylvia Rimm for advice specific to the particular challenges of gifted kids.
Have you seen 'Losing our minds: Gifted children left behind' by Deb Ruf. I reccomend reading that one for seeing your daughter 'in context.'
BTW - I think you answered your own question 'is she gifted' with your last line: no one else I know with small children would believe me.
When you can't talk to your local peer group, that's a fairly reliable sign.
I reccomend joining your state gifted association and to strongly consider getting your 5 year old son tested for giftedness. He is quite likely to be gifted also, although perhaps more in line with other family members, and you want to start learning how to be a gifted advocate with him, if needed. If you think I'm just being silly, spend some time with him in school looking at the other children, not just his friends, but all the other kids in the room.
I'm so glad you found us. I do know what it's like to not be able to 'share' locally.
Love and More Love,
Grinity
