for quick getting GUID of MOSS list/library in IE can use this small bookmarklet:

javascript:window.clipboardData.setData(‘Text’, ctx.listName);alert(‘GUID in clipboard\n’+ctx.listName+”);

for saving to your IE just click to link with right mouse button and select “Add to Favorites”

MOSS: Get list/library GUID

based on GUIDy listu, knihoven dokumentu.. and info by Patrick Tisseghem