It is never too early to start the job search process. As a current student, you can do this by reading articles about the LIS field, reviewing job ads to make note of the required qualifications, staying on top of market trends, developing your network and making ongoing efforts to stay connected with that network. It is important to start this process early in your academic career.
Once you begin your job search, you want to treat it like the most important homework assignment of your academic career. Put all of the research and information-gathering skills you have acquired in your LIS program to work developing a solid job search strategy that focuses on YOU.