i think u can use a software thingie called CVS. or visual sourcesafe. CVS is free. it has versioning control and bla bla bla bla and not that hard to use. check it out at
http://www.cvshome.org , well if you have money u can try visual sourcesafe from microsoft. however if you donj't not need anything that is so advance. u can just simply to a database system that stores the source code in text