Help Where to Promote Raffle Tickets?

My sister runs the UFO Symposium in Aztec, New Mexico, which is the second largest after Roswell. The money they raise doing that benefits the local library.

This year they are having a raffle to win a brand new Chevy Silverado truck, but one can also take the cash equivalent, which means that the raffle is open to anyone in the world that wants to participate. Tickets are only $50, which, after the truck is paid for, will go to the Friends of the Library.
She is running out of time to get enough tickets sold, and we are kinda stumped about where to go to tell people about the raffle. I am SURE there are tons of people in the world who love raffles, love UFOs, love librarys, love trucks and have $50 to spare who would like to purchase a ticket…I just can’t figure out the most effective way to find those people and let them know.

Craigs is obviously a possibility, although there’s no clear category. I think “community” somehow. And my sis has done lots of googling on the word “raffle” and “sweepstakes” to find sites devoted to that kind of thing.

But aside from that…?

Any ideas?