Praxitiles

I have noticed that when I place a cache, certain people get an immediate notification of my placement, and they jet off to pick up a First To Find. I'm not crazy about this practice, as I'd rather my caches be found casually by whomever is out looking in the area, but my question here is, how are they getting these notifications? I've searched the entire site for several hours and can find nothing about this function. Thanks

I know that the place where you can set up an instant notification is CALLED "Instant Notification Service" but how do you get to it? There is nothing on any link or any page that even HINTS at such a place! Give us a detailed step by step way to get to it. Thanks!

I have a travel bug and am trying to activate it. The form wants to know if the bug is "collectible" or not. What do I say? Why?