I\'ve been reading forums and trying Steam APIs, I\'m searching for an API which provides all Steam Games.
I found the API providing all SteamApps, and the Steam Store AP
A common method here is to cache the results.
So for example, if your using something like PHP to query the results, you would do something like json_encode and json_decode with an array / object to hold the last results.
You can get fancy depending on what you want, but basically you'll need to cache and then perform an update of the oldest.