Hey Jr
If it is your first formal letter, keep it short, so do not send 1 or 2 pages of a proposal, the first step is to get there attention on what you can do for there company and how it will benifit from there investment to you,
Outline the basics and keep it short:
ie: TV, media, apperances, and the area's you will be racing were it will benifit there company, also if your team can bring in market shares for those area's that they are not currently getting to.
Get them excited on the first propsal, if you get there attention, they will inquire to get more infomation from you, also offer to meet in person with them with more information, meeting a marketing and advertising department face to face is a huge advantage.
Don't send a generic proposal, they see them everyday. Write it as if you are in charge of there advertising company and what would get your attention to want to hear more.
Be patient but persitent, for the Coast Guard it took me 9 months, 5 face to face meetings and overcoming legal objection, everytime I overcame there last objections, they come up with a new one. The one Capt in DC even joked me, we just signed you because you would not go away.
Winnebago took over 4 months and so on...I have not got a check from any company that did not take months.
If its a major company...it will take time...background checks and so on...if its a small company and you can get referals from, it will go a lot easier.
just a little input
Gino