Depending on the methods of counting, as many as three hundred versions of  Ramayana are known to exist. The oldest version is generally recognized to be the Sanskrit version attributed to the sage Valmiki.

The Ramayana has spread to many Asian countries outside of India, including Burma, Indonesia, Cambodia, Laos, Philippines, Sri Lanka, Nepal, Thailand, Malaysia, Japan, Mongolia, Vietnam and China.

Source:
http://en.m.wikipedia.org/wiki/Versions_of_Ramayana