pubid, can be found in your OfferToro account under the Account Tab. Look for Publisher Id (pubid)
appid (the id of your App Placement), and secretkey can be found by going to 'App Placement' in your OfferToro account, then by clicking on the app placement you want to pull the feed for. Its Mandatory that you create an App Placement before you can access the API .
Secretkey is also known as App Key.
Note: Each App Placement you create, gets a separated API feed, with different appid, and different Secretkey (App Key) .
Here is an example of a live feed.
Note, this is a generic feed, make sure you use you own one !