I went through the process a couple of years ago. It was a lot of work, but it was not overwhelming. There is a form I filed with the State of Ohio first establishing the organization as a business and getting a tax ID number. I think the next thing I did was apply for a federal tax ID number. The last thing I did was apply for the 501(c)(3) status.
You don't have to be in existence for three years; actually, you are better off if you are new. I also searched online for Articles of Incorporation of different organizations to help word the one we created. When completing the paperwork, be sure to call the IRS if you have questions. They are very helpful.
I think the total cost was around $600-700, and it took a couple of months to hear back that we had received our status.