Mailing lists
Here you can access PostgreSQL mailing lists for Postgres users and developers.
User lists
pgsql-general (297307)
—General discussion area for users. Apart from compile, acceptance test, and bug problems, most new users will probably only be interested in this mailing list (unless they want to contribute to development or documentation). All non-bug related questions regarding PostgreSQL's version of SQL, and all installation related questions that do not involve bugs or failed compiles, should be restricted to this area. Please note that many of the developers monitor this area.
pgsql-advocacy (21658)
—Coordinates people working on promoting PostgreSQL, organizing user groups, and dealing with PostgreSQL marketing and PR. Also a good place to ask for presentations and flyers if you need them.
pgsql-announce (5221)
—Announcement list pertaining to PostgreSQL and various third party software.
Developer lists
pgsql-hackers (587751)
—The PostgreSQL developers team lives here. Discussion of current development issues, problems and bugs, and proposed new features. If your question cannot be answered by people in the other lists, and it is likely that only a developer will know the answer, you may re-post your question in this list. You must try elsewhere first!