This is a bit of a complicated question, but it seems like the most direct route would be to load the XML document or XML string via MSXML2.DOMDocument which will then allow you to access the XML nodes.
You can find more on MSXML2.DOMDocument at the following sites:
- Manipulating XML files with Excel VBA & Xpath - http://en.allexperts.com/q/XML-1469/Manipulating-XML-files-Excel.htmManipulating XML files with Excel VBA & Xpath
- MSXML - http://msdn.microsoft.com/en-us/library/ms763742(VS.85).aspx
- An Overview of MSXML 4.0 - http://www.xml.com/lpt/a/979An Overview of MSXML 4.0