Checkout (http://www.seo-proxies.com/?prc, please check thehttp://www.blackhatworld.com/blackhat-seo/proxies-sale/107493-new-exclusive-http-proxy-service-api-multiple-subnets-auto-browser-configuration.htmlthread, it contains a lot of information) if you want a premium solution
You'd just have to integrate the rotation API into your tool and call a rotate command at the right time (using a license providing the right amount of IPs).
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You should NEVER get blocked by google.
That's the worst you can do, it means their scripts have detected your activity.
Google blocks can come in a few steps:
1. Google will warn you about what you are doing, this step often never appears
2. Google will throw a captcha on you, warning you about a potential virus on your PC
3. Google will temporarily ban your IP, first this is often a short ban, later a longer ban
4. Google will permanently ban your IP
If you have the right amount of IPs and rotate your IP at the right moment you can hit google 24 hours a day without ever receiving a warning. That's the goal you should set as everything else is always a danger to get unwanted attention and issues.