That's a very good question, considering that they aren't on the web site, for those "notify me" links. My suggestion is to sign up for the Newsletter, which is sent out very shortly after products and stock are added.
They usually send around an email letting everyone know when new items are posted, and high demand items are back in stock. The Ultimo is definitely high demand. As well, the Newsletter will alert you when a new version of a product somes out, while those pesky "notify me" links that you find on some sites are for the current unit only.
The newsletter also gets you a discount on all purchases, so it's a win-win.