Don Jones has been known to proclaim that "If you’re parsing a string in Windows PowerShell, you’re doing something wrong."
Unfortunately, you sometimes have no choice but to work with strings. The good news is that while Windows PowerShell is an object oriented tool, it is also able to parse complicated strings.
In the September 2008 installment of his Windows PowerShell column, Don Jones demonstrates how you can use Select-String to parse strings.
Don has also provided a video demonstration, which you can watch online to see just how easy it is to parse complex strings with Windows PowerShell.