Novel plots and pitches follow pretty predictable formulas, but it's not so easy to find those formulas summarized simply. This website does a fabulous job of it:
http://www.iggiandgabi.com/2010/05/abcs-of-writing-a-pitch/. Yep, the ABCs of writing a pitch. It makes the incredibly difficult job of summarizing your 40,000-100,000-word novel in 300 words much less daunting. I still haven't figured out how to summarize any of my novels in one sentence, though. Any pointers?