Pull data from XML and put in postbit?!

[digitalJE5U5]

OK, I'm completely lost. But I know this is simple stuff for you guys. I have a Age of Mythology Clan site, and I want to put the users rating into the postbit, under their name.

I think I've found out how to access this rating, which is ever-changing by going here:

http://aom.stats.zone.msn.com/AOM_RC0/query/query.aspx?<?xml version="1.0"?><clr><cmd v="query"/><co g="AOM_RC0" s="100" z="1.0.3"/><qer id="ESO.Query.Example.68.184.73.72" np="0" nn="0" si="0" en="GX_Iron" et="ZS_Human" md="ZS_Lightning" rn="ZS_TopPlayers" tp="ZS_AllTime"/></clr>

In the example above, GX_Iron should be a variable ($post[field5]) . My problem is how do I extract the field (parse?) "primaryrating" from the above resulting XML(link has the XML) and place(print?) it in the postbit?

I've searched everywhere for this, but can't find a simple answer.

Please help.

Thanks,
/DJ