InfoPath Dev

I have a list on sharepoint which contains 2 columns. For example: column "product line" and column "E-mail" Then created a simple form with drop-down list box which takes values from "product line" column. What I want is to get in another text box the email address associated to selected product line. Please advise how to do it? Thanks !

 Hi - sorry I was so slow to see this & hopefully you have figured this out by now - but add a rule to the field bound to your dropdown that sets email to the email value in the secondary data source. Add a filter to make sure you get the right row - where the product line is equal to the selected product line. If you still need help, attach your file to a reply under the Options tab & I can give you a hand.