The full path on the server to your cgi-bin directory is as follows:
/home/<login>/www/cgi-bin
The full path to a script installed in that directory would be:
/home/<login>/www/cgi-bin/<script name>
Replace <login> with your FTP login user name and <script name> with the filename of your script installed in your cgi-bin directory. When logging in via SSH, you may notice the server puts a /usr prefix on the above path. Do NOT include /usr prefixes in references to your script paths. While it will appear to work that way, it may make your scripts break when your site is moved from one server to another (e.g. when a server is upgraded or retired).
The path to your cgi-bin from the web is:
http://your-domain.com/cgi-bin/
Likewise, the path a script installed in that directory would be:
http://your-domain.com/cgi-bin/<script name>