Expat + PHP Examples...

Hi there! I've found out that I can use expat XML, but I can't figure out HOW to use... it seems simple, but I tried and can't figure it out... I'd like to get retrieve info from http://www.frisim.com/frisim/servlet/rss?searchString=google and convert it to html... I've read a lot a of text for Expat, but found no really good example (I found one at phpbuilder.com but with links that went to xml-files that didn't exists ): Someone who have used expat.. ..and can give me a hint... /G