This is the order of problem solving:
PostgreSQL organisation is selling technical support to companies, the revenue generated will be used for maintaining several mirror sites (web and ftp) around the world. The revenue will also be used to produce printed documentation, guides, textbooks which will help the customers. They are at http://www.postgresql.org
Another company called 'Great Bridge Corporation' is doing development, sales and support of PostgreSQL. They are at http://www.greatbridge.com. It is a public company setup by 'Landmark Communications corp' and other venture capital firms to exclusively sell and support PostgreSQL to very large enterprises and corporations all over the world.
You can also take help from professional consulting firms like RedHat, Anderson, WGS (Work Group Solutions). Contact them for help, since they have very good expertise in "C", "C++" (PostgreSQL is written in "C") -