I don't know about cache but the strange thing is I can not see the impressions in Google website for couple of days back and people do come from google which I have seen in Google Analytics, so something is going on with Google.
For getting Google Adwords API, You need to provide Google with a bunch of information about your PPC clients and need to satisfy its RMF (required minimum functionality) https://developers.google.com/adwords/api/docs/requirements - all this need to shown while registering for API.., After submitting all the above stuff, Google may or may not provides API key along with price.. Let me know if you find any adwords PHP script provider who provides licensed API Tool? Thanks..
I don't think there is way of using the Google AdWords API commercially without also implementing the Ad management functionalities according to the terms of service. However, the strange thing is that I see a lot of online services do just this (they didn't implement the ad management functionalities). Can anyone confirm that it's not possible to use the AdWords API keyword suggestion or estimation services without ad management, or is there another way?