We don't have much in the way of PokerWiki-specific help, but in general we try to mimic the standards of Wikipedia except that, obviously, everything here is about poker. We also have a bit more tolerance for point-of-view, although where possible it's still good to edit articles for neutrality.
Wikipedia uses the same MediaWiki software, so most of their help pages are applicable. See especially Wikipedia:Wikipedia:Tutorial and Wikipedia:Wikipedia:Your first article (but don't worry about the 'original research' exclusion; we'd be delighted if you want to post source material for your doctoral dissertation.)
Useful stuff Edit
Here's a helpful link if you're trying to make nice looking tables: