XPath and Configuration

[venerable bede]

VS 2005
Hi All,

I have a small config file :

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
  <connectionStrings>
        <add name="ProgramService" connectionString="http://SERVERIP/WebServices/myservice.asmx" />
  </connectionStrings>
  <appSettings>
          <add key="loggingLevel" value="4" />
  </appSettings>
</configuration>

And would like to edit both the "ProgramService" connection string service and the value of "loggingLevel" in the appsettings using XPath.

Can someone point me in the right direction ?