Were there any negative "side effects" (for lack of a better word) to the castor oil for you? While I *really* want to go on my own, same as you, I would much prefer a "natural" induction than a medical/hospital one, if I had to go that route. (Which may or may not even be an option for me, as some hospitals won't induce VBAC.)
I actually had really good experiences with it...most of the time it never even sent me to the bathroom! I think the "horror" stories associated with it are people who are taking far too much, far too frequently (or all at once), and without much caution.
With DD2, I took it at my EDD (VERY high Bishop score...I tend to dilate a LOT beforehand- like a full 5cm, efface well, baby is always engaged, optimally positioned, and in a very favorable station, etc). I took it before bed once, it didn't do ANYTHING, not even send me to the toilet. Tried again a few days later before bed, and at 3 a.m. I was up, in labor, never had to use the bathroom, and she was out in 4 hours. A VERY wonderful unassisted homebirth, no complications whatsoever before, during or after, labor went amazingly and I pushed her out very quickly.
With DS, again, my body was well prepared for labor (dilation, effacement, position, station, etc). Right around my EDD again I tried the CO. This time it was out of sheer desperation- I'd had a VERY painful pregnancy with SPD pain, SI joint trouble, etc, that no one I saw could really remedy, and I'd been having weeks of REALLY intense prodromal labor (waking up in the middle of the night with transition-like contractions for hours at a time). Again the CO worked, I went into labor around 3 a.m. again, I DID have to use the toilet once but it was a very short, "mild" experience, and by 3 hours I was complete (though he wasn't born for another 6 hours, I believe he shifted a bit and may have been asynclictic at that point as my pelvis adjusted to the size of his head!!!!). Once my body had put on the "final touches" and I broke my own water, he was out in 2 quick pushes. Again, a wonderful unassisted homebirth.
So it's worked wonderfully for me each time.