K&P - Thanks for the info.
I have also noticed some day's she has a little limp going in her back leg. I put it down to her and Rex playing rough - he likes to drag her off the couch by that same back leg. I've been trying to get him to stop, if i see him going for her leg i clap my hands and tell him 'argh'. She also lay's with her back legs spread out behind her - like a hung chicken, which i have been told is a sign of good hips? I'm not too worried that there is any serious joint damage or anything (i'm not even too sure what i should be looking for?), i'm just worried that doing too much physical activity with her at her current weight isn't particularly good for her which is why i was looking at hydrotherapy.
I have a day off work tomorrow so i will be getting in contact with a few of the above mentioned places. I definitely want to get in touch with these guys Thelinks.net.au - service details as they seem to be the only one's who offer help in the weight loss department. I don't know if i should head straight to the chiropractor just yet as i'm not sure anything is wrong. I mean she delays when jumping on the bed and in the car - she will just put her front paws up as if to say 'lift me up' dunno if that's just plain lazy or what. She doesn't seem to be uncomfortable or in any pain?