Build a form that returns to the parent window

Hi guys, I have been working on a project for some time now and I'm trying to make a form that includes (many things and) an edit box with a button by it. I want this button to open a pop-up window and include a search form that queries a database and return to its self the result set in a table in which the last cell contains a link (or button). This link should return to the parent window a value of this specific row. Well I have build the whole interface and since php is server side I thought I could write this including javascript. Non of my experiments worked because the pop-up window does not returm to the parent window something. I searched through the web and nothing seems to do the magic for me. Please any suggestions would be welcome cause I have been working on this for several hours as we speak. -- Thodoris