I know this isn't the case for everyone, but for me, having tats on the bone hurt the least. I have one behind my ear and 2 on my lower hips. The one on my head hurt the least, and the hip one that goes up a little bit onto my stomach KILLED! But I agree with everyone who says that the pain should not stop you. If it does, you probably don't want that tat bad enough
As to where, I personally loooooove tattoos on ladies back ribs/side, inner wrist, inner bicep, and hip bones. I think the "how much should I loose first" question should be answered depending on where you want it. How does your body look in that area now, what do you want, etc. A decent tattoo artist should also be able to give you some idea of if/how your tattoo would change depending on how much your body changes.