hi

not entirely sure I understand your requirement - could you detail it a bit more please?

I have three separate list, each list has an Assigned To field, I want to be able to create one task notification.  The email can contain links to the 3 separate list and to the Task list, which would have a view of their tasks. 

Ah ok I see. not sure how you would be able to tell from each list if notification has already been sent out.

but have you looked at the Nintex workflow web parts - tasks assigned to me?  that is a good place for a user to go to in order to see a list of tasks rolled up across the scope you desire (site, site collection, farm) assigned to the logged in user.

My thought was I could create a workflow with a flexi task, that creates a task for each "Assigned To" from each list (the 3 list are not Task List, they are just a custom list) in one Task List (all three tasks have the same Due Date), within the body of the Task email, would be a link to each list and a link to the Task List (which would be grouped by user...I'll look into the Webpart you mentioned).  There will be an initial email that goes out 90d before Due Date, Reminder if not complete 60d before Due Date and a Final Reminder 30day before Due date if not complete.

Can I do a site workflow (or a workflow on one of the 3 list) query each list and get the Assigned To field (there will be duplicates, so I would only want to send 1 email, but have a task associated with each item they are assigned.)?

Hope that makes sense.

Thanks

Kim