Open Question: How can I contact someone like Bill Gates with a proposition - for eg: an idea that can be a huge success?

I've got this idea that has high potential, if it gets implemented.. It requires good administration and capital to get it done. When it comes to operation, it could be of great help to the people, and possibly the whole society. The system is more related to the internet and networking field. So, I would like someone, who would really take his/her time to read through my report and assess the benefits of my plan, and can make it happen. I would like to contact major companies like Microsoft and Google, regarding my idea. How can I contact the higher personnel (in Google, Microsoft, etc)? If possible, please get me their e-mail address (or mailing address). I went through some of the resolved questions related to this topic. I have noticed that some of the experts on the topic have mentioned about patenting. They have stated, if my idea isn't patented, the company could steal my idea and I could sue them. And, due to this reason, some companies don't even care to go through ideas which are not patented. Is ithis true? And, relating to my proposition; my idea is not an invention and does not have anything to do with technology? It can work fine on the current technology that is available. Would I be needing a patent in this case?