Finding "strategic partners"

I have a product being sold out on the market that is a key drawer. You put
a key on a special fob, put the fob into the drawer, and the computer keeps
track of the key. For example, this thing is being used by car dealerships.
Say that a salesperson wants a key. He walks up to the computer, tells the
computer which car he wants, and the computer lights up the key fob and
unlocks the drawer. ( http://crmsecurity.com is one of the companies that
currently sells this product.)

There are other markets for this product. For example, jails, motor pools,
airport, car rental outfits like Avis and Budget, etc. I also see a new
niche market for this product that my competitors have yet to see
(shhhhh.... I can't say what it is. They are verrry sneaky).

I really don't have the resources or the contacts to go after these big
places. My thought is that I should find a company that, for example,
installs all of Budget Car Rental's computer networks and work with them.
These places have the inside track, and I know that my product has the
potential to bring a lot of profitability to sales for these companies.

But.... how? How do I find out who does Budget's computer networks, or Los
Angeles Airports security systems, or UCLA's car pool system?

I've thought about trying to go directly to the buyers for these big
companies and asking them who does what myself. I'd rather not take that
approach if I don't have to because I might end up having to go to these
people in the future, myself, if my little strategy doesn't work out, and I
don't want to screw up my positioning.

Any suggestions?

Mike