Hi SethMW,
If I understand you correctly, you want to insert a Hyperlink control and have it point to a local file. When you insert your hyperlink control, right click and click Edit Hyperlink. Enter your network file path in using this syntax - file:\\yourServerName\folder\filename.txt. You will need to make sure that the file is in a folder that is shared if users will be accessing the file from locations other than the server it resides on, otherwise users will get an error when they click on it.
Hope this helps. Let us know if you need any additional help.