Some solid guidelines from James Scott Bell. I especially love what he says about backstory.
Another from JSB. How to write an eating scene.
This says it's about beta readers, but it could just as easily be titled "where to find critique groups."
(BTW, I highly recommend Critique Circle. The site has a great structure and lots of writers at every stage of development.)
If you're at the stage where you have or are developing a mailing list, this is a useful post