There is a good handbook page dedicated to this topic you should read before posting a job in this forum.
Your posting should also include which parts of your project the developers will be allowed to contribute back to the Drupal project. Projects which allow the developer to contribute back to the community are preferred.
If you would like to speak to someone right now, please get an IRC client and join irc.freenode.net server, and join #drupal-consultants. There are consultants in that public channel 24/7.