A really DOM question

Question

very new to the java DOM and here's my (I expect very simple) problem:
I have parsed in an xml file and created my DOM document.
I have searched through the document for the required node.
Now I want to write this node, and all its descendants, out as an xml string - how? There doesn't seem to be any toString(), write(), save() or similar functions on nodes, elements, documents etc

Answer 1

thanks to all, bbritta gets the points (as I don't have any of the books to hand)
The actual code I have now used:
TransformerFactory transFactory = TransformerFactory.newInstance();
Transformer xslTransform = transFactory.newTransformer();
Source xmlSource = new DOMSource(myNode);
StringWriter xmlStrWriter = new StringWriter();
Result result = new StreamResult(xmlStrWriter);
xslTransform.transform(xmlSource, result);
String myResultStr = xmlStrWriter.toString());
Somewhere along the line it has added a
<?xml version="1.0" encoding="UTF-8"?>
tag to the front of the result string, but I can cope with that