They have Supernatural conventions in a few locations across North America, you could see if they're having one near you or keep an eye for one next year (I know they've already held a bunch for this season). They also do Comic-Con but that's probably significantly harder to get into.
How about you follow Jensen Ackles/Jared Padalecki (Sam and Dean Winchester respectively) on social media? Like Facebook and twitter (especially twitter), and ask them directly. Perhaps you can also go to their shooting locations (They shoot and film the show in Canada). It maybe expensive, but it could be fruitful! Lastly perhaps you can write letters or record a video (video would be better), or go to and reach out to places that Jensen Ackles/Jared Padalecki will be in. Like conventions, talk shows (Like the Ellen Show), and stuff like that. Also find out if and when they will be in your country.