lammert - 6:59 pm on Nov 8, 2010 (gmt 0)
The path is in the environment variable PATH. The place where you add an extra directory to your path depends on the shell you use, but it is probably the file .bash_profile or .profile in your home directory.
You can extend your path by adding the following two lines to the profile file:
Be sure to logout and login again, because the profile file is only read at login.