Not cheap, but you can order a dozen replacement disks from KitchenKrafts.com. But if it CAME missing one, I'd contact the seller (Amazon?) customer service - maybe they'll send you a replacement bottom.
You may find the Mini Cherry Cheesecake recipe at pinchmysalt.com
There are also a few mini pumkin recipes floating around if you just search for mini cheesecake you are sure to find a few using the Norpro pan. That is how I just found the two recipes I am talking about.
Good Luck! And enjoy!
I've tossed the box but found Norpro on-line at www.norpro.com.
They are a US company however I cannot find where the products are actually manufactured. You can contact them at Norpro Corporate Offices. Hope this helps.
2215 Merrill Creek Parkway
Everett, WA 98203