Unfortunately it won't get a whole lot easier either. Custom packages are made to simplify a task for other people. I can appreciate wanting to build yourself though.
The first place to start when dealing with protocols is to go to the rfc defining the protocol and how communication works with it. FTP rfc is http://www.ietf.org/rfc/rfc959.txt
. If you have a socket set up already and can move files, then chances are you are where you need to be. The command to send to a server to delete a file is DELE.