How To Retrieve Specific XML Data

How To Retrieve Specific XML Data

I want to be able to retrieve specific xml data from a specific website and then update the values of other fields on my form with that data.  I have been messing around with the executexpath and get url commands, but I cant seem to grab the data. 
 
So basically, I have a form, and when a user types in his ID number, an xml file is called, to retrieve other data.  For example:
 
ID:
Name:
Age:
 
When a user types his ID in, I want to poll a live xml doc on the web, ( http://www.domain.com/(ID).xml, where the ID the user typed in is also part of the url of the xml doc i want to query.  Then i want to query the 2 xpaths of name and age, and fill the data in accordingly.
 
I wouldnt think this would be very difficult so hopefully someone can help me!
 
Thanks in advance.