Work through online Latin lessons that are offered for free. The Latin Course for the School of Virtual Languages offers several Latin courses online for free. Entire textbooks are also available online, such as the New Latin Grammar for Schools and Colleges.
Check out a Latin course from the public library. Books, tapes and CDs containing Latin lessons can help you learn the language. However, remember that you have to return the Latin course after a couple of weeks. So library materials are not necessarily good for long-term reference or learning.
Watch free Latin lesson videos available on YouTube. Search for "learn Latin" on the YouTube site to find a number of Latin lessons for you to watch.
Read online texts of Latin manuscripts. Some of the world's greatest literature was written in Latin. Try reading through free online Latin texts, or check out a book written in Latin from your public library.
Join an online group devoted to students of Latin. Become an active part of the community. Exchange ideas and questions with other students, and help each other read and translate Latin texts.