Kate gave me this link the other day, which may or may not be of help... I haven't had to really try to use it yet.
And also the FAQ's here at LJ will give you the code setup for most things.

And another thing... do you use Firefox? If so, go here for the LJ Hook add-on for Firefox. It allows you to simply right click and choose from a drop-down menu to do some coding. (And yes, it's been working for me lately even in the HTML editor of posting entries...)