This article is from the Car Audio FAQ, by Ian D. Bjorhovde (firstname.lastname@example.org) with numerous contributions by others.
Ah, the green grass on the other side of the competitor's fence;
sponsorship. Sponsorship is not the easiest thing to obtain. And it
might cause more problems than you anticipated. Obtaining sponsorship
really depends on how much dedication you show for competing and finding
the right manufacturer sponsorship deal at the right time.
Keep in mind that car audio manufacturers consider sponsorship a form of
advertising. Each manufacturer has a different policy concerning
sponsorship. They are looking for a competitor that has shown they are
committed to competing for a long time. They want someone that has
shown that they know how to win, but also, how to handle defeat
gracefully. They want someone that is well known in competition
circles, someone that new competitors can come to and ask questions
about the system and the manufacturer's products. They are basically
looking for people that will put their product out there for people to
see and help sell the equipment.
As a competitor, you must show that you are committed by to going to as
many shows as possible. You must open up your their vehicle and show
off the system. Manufacturers want a show system, which often means
turning your vehicle into a "trailer queen." That may require you to
buy a trailer and tow the vehicle to the shows you compete in (this also
means that you may need a new daily driver). And of course, if your
bought equipment below retail or were given the equipment, then you will
be forced to compete in the Pro or Expert class.
There are different levels of sponsorship. It usually starts with
manufacturer technical support. The manufacturer will give direct
technical assistance to the competitor. At larger shows, they may
reserve a space for you in their "tweek and tune" area.
Next, the manufacturers may let you buy equipment from one of their
dealers or the factory and a discounted price. This will definitely put
you into the Pro or Expert class. Some manufacturers will let you mix
and match equipment from different manufactures. Others want you to use
their equipment only.
Then the manufacturer might start giving you equipment and providing
some or all of the installation costs.
The holy grail of sponsorship is when the manufacturer provides the
equipment, installation, and pays some or all of your competition
expenses. It takes a lot of money to travel to shows. By the time
someone reaches this level, they are frequently hired as an employee of
the manufacturer. This is a good way of making the car audio business