First of all you'll need a domainname. (and just in case) Seeing that the link you showed as example points to localhost, you will need a webhost (since opening up your PC to the internet is a very bad idea (without proper knowledge, and even with).
So the answer is: get webhosting + domainname.
Spelling is freeware, which means you can use it for free.
On the other hand, it is not open source, which means you cannot change it or publish it in a modified form.