Try what ryan.stewie wrote.
Go to Control Panel and click on Administrative Tools. Open the Services tools and find Apple Mobile Device. Double click and make startup type automatic and click start, if it isn't. Try to see if Itunes gets it now.
If not, go to Control Panel, System and open Device Manager. Under Universal Serial Bus Controllers, uninstall Apple Mobile Device drivers. Then plug your Ipod back in and it'll reinstall.