There is a great step-by-step post for finding the Shared List Asset ID using Program Builder. However, while teaching at EE13 todd.sprinkel opened my eyes to an easier way to locate the IDs for Shared Lists.
Asset IDs can be handy. Here are just two scenarios where you might crave the Asset ID.
Locating Shared List Asset ID:
Side note: Campaigns, landing pages and emails all have the campaign ID in the URL at the top of the editor screen. Super easy. You just navigate to that asset inside of Eloqua and check out the url in the address bar when you arrive.
Locating other Asset IDs (such as Campaign)