Hi Kellie,
Currently, I don't have any scripts available for migrating items within OnTime, but its definitely possible. If this is a solution you'll need to use frequently, I would suggest to use the OnTime SDK. One of your developers could quickly write an application using the OnTime SDK, rather than digging deep into OnTime's database schema. Also, working with OnTime on a database level is generally not recommended outside of our Implementation Services.
What sort of process are you using that would require bulk moves of items? Knowing a little bit more about the process might help to explore other options.
-Nathan