Fortunately, you can do more than just get blown off by the dealer (if you feel like that is what happened to you). Visit the US Dept. of Transportation's complaint system and file a complaint with their Office of Defects Investigation (ODI):
What this does is put information into the database that DoT uses to look for unsafe trends in vehicles. ODI conducts defect investigations and administers safety recalls, and this database is a primary source of information for them. Putting in an entry does not mean that anyone will necessarily get back to you about your particular complaint, but eventually if enough drivers have similar problems with a particular vehicle type, ODI is supposed to investigate. You should be sure to use several different words and phrases to thoroughly describe your situation since often this database is searched via key words. (That means that if they are looking for a particular trend they might only look at records that contain a specific word or phrase, not all records for that vehicle.) You should include specifics, and in particular things that you can recall that would suggest it is not simply driver error. But, realize that the description you type in will be publicly available, so think about what you write.
To be sure, this should not be the only thing you do. If you believe you have a problem with your vehicle should talk to the dealer and perhaps escalate things from there. (If it happened to me I would at a minimum demand a written problem report to the manufacturer central defects office be created and demand a written response from the manufacturer customer relations office to leave a record.) But, if you skip the DoT database then one of the important feedback mechanisms independent of the car companies that triggers recalls won't have the data it needs to work. If you had an incident that did not result in a police report or insurance claim reporting is especially important, since there is no other way for DoT or the manufacturer to even know it happened.
Even if you haven't suffered unintended acceleration, you might be interested to look at complaints others have filed for your vehicle type, which are publicly available. And of course you can report any defect you like, not just acceleration issues.
I recently came across the web site: http://www.safercar.gov/
This has general car safety information and also has a way to file a vehicle safety complaint, including a specific page for filing a safety complaint (https://www-odi.nhtsa.dot.gov/ivoq/). One would hope the data ends up in the same place, but I don't have information either way on that.
(For those who are interested in how the keyword search might be done, you can see a NHTSA Document for an example from the Toyota UA investigations.)