How to inform/attract more candidates for a postdoctoral position?

Possible outlets I can think of include:

• Field-specific e-mail lists
• Department email-list forwarded through collegues at other departments
• Adverts inserted in talks/presentations held by people at your department (e.g. at invited talks, conferences etc.)
• Job ad websites (national and global)
• Advert at research-focused web communities/forums, such as Researchgate and Academia.edu, as well as LinkedIn.

There are sometimes subject-specific mailing lists available on which one can post job advertisements. Examples that I am currently subscribed to are All-Acad.com ([email protected]) and allstat ([email protected]).

I can't say whether this is a more effective way to advertise, though.

ADDENDUM: Actually, I think it would be useful to expand the question in the following way, that would be useful for both prospective employers and job-seekers. This could be a community-wiki style question. So, the question could be: what resources are available for job advertising? And each answer could be for one subject, and divided into free and non-free sections, and within each could be web sites, mailing lists etc. I don't know whether such a question would fall within the scope of this site. I do know the SE sites vary in their policy wrt such "list" questions.

In some departments it is common practice to publish available postdoc positions in other institutions via the departmental mailing list. You can try mailing administrators/faculty in relevant departments.