First, know that your local Toyota dealer has the most to gain by solving your problem. By making you happy, they are the likely to be the recipient of all of your future business. In fact, dealers know that solving customer service problems is a great way to make a lifetime customer and they will often go above and beyond to help.
However, this doesn't mean that a dealership will solve every customer service problem free of charge (or even solve them at all). If you want to get your problem solved, you're going to have to convince the dealership that you're going to be a good future customer and give them good publicity.
The best way to convince a dealership you're going to be a good customer in the future is to show them you're a good customer now. When working with anyone at the dealership, be nice. Let's admit it -- sometimes it feels good to yell at someone. But if you want to get the best customer service you'll need the people at the dealership to like you. "Kill em' with kindness" and you will prove you're a customer worth saving.
Being nice is crucial, but speaking with the general manager of the dealership is easily the best thing you can do to help yourself. While there are many managers in a dealership, the GM has the power to solve nearly any problem. The GM can pick up the phone and speak with one of Toyota's regional executives, authorize an expensive repair, or even decide to warranty a vehicle. Toyota empowers every dealership general manager to act on their behalf -- perfect for solving customer service problems.
If the GM at your local dealer can't help you, your next point of contact is Toyota Motor Company. I suggest you try a two-pronged approach and call both your local Toyota regional office and the national help line. You can find the phone number for the national helpline in your owner's manual, and the local regional office can usually be found in the yellow pages of your regions larger cities. While the local regional office will often refer you to the national helpline, with a little persistence you can speak with a regional executive about your problem.
In summary, when you have a Toyota customer service problem, start by working thru your local dealer. Speak with the GM and be as nice as possible. If your local dealer won't help, call both the national Toyota hotline and the closest regional office. Be nice, don't give up, and your Toyota customer service problem will be resolved.