SERP Checking Script using Google API

We are looking for a tool to check search engine rankings on major search engines. The tool will be free for people to use on our site so it will need request a google api in order to provide results from Google. The final tool would something similar to [login to view URL] but using the new api. If it's not possible to use the Google api we would still like a similar script to check rankings. Ideally we're hoping someone out there aleady has the script developed. Thanks for your interest.