What is the chance I could get an immigrant or skilled-independent visa in Australia?

Do you have a 3 year degree in Nursing (does not matter if from college or university) -- is it 3 years in lenght? If so your qualifications may be able to be transfered to Australian (Check with the College of Nursing in NSW) - f it was shorter than 3 years - its likely that any qualification that you have is not accepted as a nursing qualificiation and you will have to retrain as a student.