It's possible to hire a company or an individual for custom development and support. There are a lot of companies that use MediaWiki in their solution or specialize on developing skins and extensions. See Professional development and consulting for the details.
This is the place to come if you want help using the MediaWiki software. All the content in this section assumes that you have access to a fully set up and working version of MediaWiki and are looking for help using it to view and create content.
These pages are in the early stage of development. If you can't find the information you are looking for, or have found useful information somewhere we have not linked to, then please leave a comment on the talk page and someone will look into it.