Here is a list of the help/tutorial/policy/etc. pages that I have found useful (roughly in the order that I think they should be read as one goes from novice to experienced):
- Citing sources tutorial video
- Help:Citation_tools
- Help:Contents - Master help page.
- WP:Policy - Entry point for policies and guidelines
- WP:Quality - Quality scale for Wikipedia articles
- Help:Magic_words - Variables you can use in templates
- Help:Templates
- Help:Sandbox_tutorial - How to create a user sandbox
- mw:Help:Magic words - More complete reference for magic words
- mw:Help:Extension:Parser functions - additional parser functions, including conditional expressions
- Wikipedia:Annotated_article - Very nice sample article, with annotations, describing a few of the conventions for how articles should be formatted.
- Wikipedia:Be_bold
- Wikipedia:Cheatsheet - concise page of examples of wikitext
- References for beginners
- Wikipedia:Tutorial
- Help:Page_history - Tips and tricks re the "View history" page