Hi InfoPathProblems and welcome to our forum!
Have you looked at the Asset Tracker solution in InfoPath 2003? This shows how to use a button to access details for a table. A little different than what you want, but a good reference since several of the concepts are similar and you should be able to reuse them. Unfortunately, you can't insert values into a repeating table programmatically without manually editing the view's XSL (to add an xd:action="xCollection::insert") so you will have to write some code to do this. Let us know if you have more questions after studying the code in the Asset Tracker sample. Good luck!
Patrick Halstead
Project Manager at Qdabra