After many many hours trying to figure this out and searching through what seems like every related support thread, I have decided to ask for help.
I'm using a modified Twenty-Twelve theme, and my developer has completely disappeared off the face of the earth. My problem, like many others, is that my sidebar is at the bottom of the page. I am sure that there are no </div> mess ups, and I think that the issue is somewhere in my CSS (no idea where).
I'm hoping to get this site up and running, but I'm just not able to battle this issue. I'll happily post any snippets you need. My knowledge of CSS is absolutely rudimentary.