@donasmrs-- I recommend a graduated bob. A graduated bob has a shorter back and slightly longer sides. This kind of cut has a lot of layers in the back and it will make your hair look thicker with more body.
I also have fine, limp hair and I got a graduated bob cut a few weeks ago. I'm so happy about it! It doesn't need much maintenance. I just blow dry it straight after a shower. I also have a round face, so the longer strands on the side and front make my face look a bit longer. The back looks very full. I think this haircut makes me look younger.
Just make sure that the cut is not too short. The back will naturally be shorter, but the very front of the haircut should reach half-way on your neck. I saw a very short graduated bob haircut the other day. The front of the haircut was reaching the woman's cheeks. It was way too short and it actually made her look older. You don't want that.