If you are looking for a good, free app to help you manage novels with lots of scenes and characters, yWriter 5
(written by science fiction author Simon Haynes) does the job admirably.
If you keep it all in your head, OpenOffice.org
is an exceptional office suite.
If you type like a fiend and have a gaggle of trained monkeys to clean up your output, Notepad
works in a pinch.
Note: Being a writer, I tend to go for cheap or free. The commercial solutions may be better... or they may not. The most important thing is for you to be comfortable enough with whatever software you use that you don't waste your productivity thinking about the software. Save your energy, so that you can focus on your writing.