Have you ever missed out on an ebook that you placed on hold, because you didn't see the email telling you it was finally available? Overdrive ebooks now offer an option to "automatically borrow" a title when it becomes available. Visit Overdrive, and find the title you'd like to place on hold (the little gray book icon on the cover tells you it's currently checked out). Click the orange button that says "Place a hold."
In the next screen, be sure to check the box that says "Automatically borrow this title when it becomes available."
When the title becomes available, it will show up on your library bookshelf, and you will receive an email letting you know.