Taking the next step

Start weight: 72.9kgs
Current weight:62.9
Height:5'4" (165cm)
Age: 35

I want to get down to 60kgs. I'm starting to think about the next level. I was looking on some gym pages on Facebook and saw some pictures of some very fit girls who were not body builder types and I started to wonder if that would be something I could do, to a lesser degree. After having 2 kids, I know I'm never going to be a fitness model, however, I would like to see some more definition when I look in the mirror.

I have done some light reading regarding nutrition and weight training and I have realised there is a mountain of information out there. However, I can't seem to find a beginners guide. Everything I have read seems to assume a base level of knowledge. I don't want to go into anything blind. I understand that you never stop learning, but I don't want to put together a new regime only to find I am wasting my time, or worse yet, buying supplements I don't need etc.

So if anyone can provide me with some web links of the basics, I'd really appreciate it :-)