Getting started documentation -- https://developers.google.com/compute/docs/api/prereqsBilling - http://code.google.com/appengine/kb/billing.htmlFeatures - http://code.google.com/appengine/docs/features.htmlWhy App Engine - http://code.google.com/appengine/whyappengine.htmlVideos - http://code.google.com/appengine/docs/videoresources.htmlSample Apps - http://code.google.com/p/google-app-engine-samples/Good list of which APIs are implemented on which languages, Python or Java or bothhttp://code.google.com/appengine/tools_tips.html