One of Walter's comments had me searching for grammar rules for capitalization. Do I capitalize 'Sir,' when used as a direct address in dialog. The answer, and others like it, can be fund on the following website:
If you have other useful, usable links, feel free to add them to this page.
From KC -
Here's the basic rules page for number usage.
Twentry vs. 20, that sort of thing.
Rules For Fixing Comma Splices and Fused Sentences
Writing with Precision
English punctuation calmly demystified
From Walter: So what's the answer about the "sir" thing? I couldn't find it at the link given...