Connect to proftpd remotely to upload files

[Larry Wells]

I am trying to set up Ubuntu 9.04 so that I can upload files to it from
another computer, not on the same network.  I have gone through and
configured proftpd and have a user.

Here is the config file http://paste.ubuntu.com/216007/

I am just not sure how to set up the ftp program on the other computer
so that I can connect to the Ubuntu machine.

Thanks in advance