Mystery authors have followed the lead from romance, and launched their own auction for the same purpose. They have a lot of the same type of stuff, like signed books, online events, consultations for authors, and book themed jewelry. You can also bid on being written into various future books as a murder victim, super villain, pet (!), or another character, in books by Andrew Child, Karin Slaughter, Sara Paretsky and others.
Here's the auction:
https://www.32auctions.com/MysteryLovesGeorgia
(I think items are still being added, so you might want to check it out more than once.)
Romancing the Runoff raised more than 470 000$ in the auction + donations, by the way!
