I can certainly sympathize with you that you'd like your baby to be born without having surgery. However, an induction is an induction, whether it's done with things that grow in your garden or things that were made in a pharmaceutical lab. There are conflicting stories and information out there regarding castor oil. Some people say that because the mother can become stressed from frequent bowel movements which can dehydrate her and major pooping cramps which can stress her out, that leads to stress in the baby and because of that, castor oil shouldn't be taken internally. There's others who say that it's a 50/50 crap shoot ... so to speak. 50% of women have diarrhea, cramping, and labor and the other 50% just have diarrhea and cramping. Others don't believe that and say that it's a miracle inducer.
There is a method of using castor oil, however, which leaves out the woman having to ingest it: some women swear by soaking a towel/rag in castor oil, ringing it out, heating it in the microwave and then placing it on the lower segment of the mother's abdomen, by the mother's pubic bone will bring on contractions.
However ... and that's a big HOWEVER ... you were 37 weeks when you posted. 37 weeks! Babies can come just fine after 37 weeks and be born vaginally after a cesarean. Unless you have the baby outside of you, you cannot weigh a baby accurately. We've all heard stories of babies supposedly being 10 lbs and coming out much less and babies suspected of being itty bitty who come out quite sturdy and large. Unless the doctor has some super duper machine or super duper powers that no one knows about yet--and I doubt s/he does--then it's impossible to accurately weigh a baby in utero.
I'm actually a little proud of the doctor not discussing induction with you! She may not know much about castor oil's use for induction and that may be her reason for not discussing it. She wants to be on the safe side and probably is not going to commit because it could put her in a tricky situation malpractice-wise. She's covering her butt.
I realize you are afraid of surgery, but the urgency you feel may transfer to baby and the message baby's getting is not "Come out, come out, wherever you are" but "Stay inside! It's unsafe out here!!" Do you see how that can come across to a baby?
Some women have tried massage to help relax them in these later weeks of pregnancy. Others use acupuncture as a way of tuning up the body, getting chi to flow without stagnating. And still others just try to chill as much as they can until that baby decides to make an appearance. I'm not saying it's easy ... especially with others kids at home.
There are a lot of women who come to these boards seeking induction help. There are no quick fixes and midwives can't waive herbal wands and have babies come out. I'm in no way chastising you! But perhaps others reading about these kinds of things will realize that babies come out when they're cooked, when they're ready, and when they feel safe. Unfortunately (or maybe fortunately), we can't predict when that will be.