Need some direction on a project

I am kind of at a loss on where to start. I have written a program that logs results to a text file. One line at a time. It is as plain and simple as that. Now the boss has upped the ante. This progarm could be running on 300-400 computers scattered anywhere in the country. Now he wants a program that will merge all of these individual logs on each computer in to one big log at the home office. I am at a loss on where to start.

  These logs are set to delete themselves when they reach 5MB in size and I don't want to copy the entire file to the home office. I was thinking along the line of somehow keeping track of which lines in the log were already transmitted so I can re-start the transmittal at any given point. Something along the line of a FIFO.

   I also need a method of sending these "lines" in the log. Some are connected via VPN. Others just have internet. I am at a loss on where to start. I was looking at inet functions but it seems like they are only applicable to entire files. Any recommentions on where or how to start this little project?

Thanks!