Talk to your accountant.
I am partial owner in two businesses along with my racing business. The main business is a medical equipment installation and service co that pays an annual advertising fee to my racing company.
My racing company, Kerns Racing LLC is set up as a racing and advertising company and it lives and breaths just like any other company. And like any other company you will need to spend some money to legally set it up with both the federal and your state goverment. The best way to go is to have your lawyer set it up ($$$), so all the paperwork is filed properly and you have the proper documentation (corporate record book, seals, stock certificates, etc). Yes, it cost money up front but the last thing you want is to have the IRS question your business status. I offer advertising on my web site, on the car and trailer along with handing our flyers and freebies at the track (I'll bet I could talk just as fast as John Force if I got a ESPN TV interview!) along with just about anything else my customers request (for a fee!). You have to think of the people who pay you money are customers, not sponsors!
As far as the 3 out of 5 year rule, our accountants advised us that as long as the business is growing ( assets are increasing) and it is being run as an active business with the intent of making a profit (ie Gross Income Increasing every year) it can continue to run. The 3 of 5 rule is for the guy that has no intent of having a real business, just a shell to take deductions.
There is money out there to be had, but don't believe for a second that everyone will "Sponsor you race car". Mosty companies don't care about the car and your racing, they care about the customers that your operation will bring to them and the return on their investment.
Steve
www.kernsracing.com