http://en.wikipedia.org/wiki/Modular_connector
The
4P4C connector, is popularly, but incorrectly, called
RJ22,
RJ10, or
RJ9.
You can buy small packs of the connectors and the 2 pair flat cable from places like Jaycar. They also have crimp tools in a range of prices. Not hard to strip and crimp your own with the flat phone cable.