Great site to give you an idea of appropriate body weights
I was trying to work out what weight I would ideally like to shoot for and I came across this fantastic site where you can type in your height and a weight and it will show you a range of images of real women at that weight. I played with it for a bit and decided I want to end up in the 130s which puts me at the top of the healthy weight range. Go have a look - its quite inspiring
http://www.mybodygallery.com/search.html?height=5+2&weight=120&pant=any&shirt=any&zphoto=Large&new=1
http://www.mybodygallery.com/search.html?height=5+2&weight=120&pant=any&shirt=any&zphoto=Large&new=1