Google AJAX Search APIが Deprecatedになっていた

で、代わりがJSON/Atom Custom Search APIらしい。
でも1日100リクエストまで。

JSON/Atom Custom Search API - JSON/Atom Custom Search API - Google Code

Important: The JSON/Atom Custom Search API requires the use of an API key, which you can get from the Google APIs console. The API provides 100 search queries per day. If you need more, simply request additional quota from the console.

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