Hey Heather -
What market are you in? I'll be honest...some markets are MUCH harder to source talent than are others. That said, when I was looking for my recent position (which I started just a few weeks ago), I searched LinkedIn. I found it to be much more thorough and up-to-date with opportunities than other job sites out there.
To Pierce's point, definitely post the job here on the community. Also, consider tapping into the local Marketo User Group (MUG) if there is one in your area. Also, reach out to your Marketo rep...they may or may not have some other suggestions and/or relationships with consultants that know people looking for a new position. You're going to find it's a very small community! 🙂
Job titles worth using: Marketing Automation Specialist, Marketing Automation Manager
Don't be scared to have your recruiters tap prospective candidates with experience in other platforms as well. And depending on your CRM integration, certainly look for those skills as well.
Good luck!
Ashleigh