Adobe does a pretty good job of introducing folks to the software as a whole and getting you started with some example projects that might be pretty close to what you’re looking for. You can find them on their site under Support (link for Flash specifically), other than that you might want tutorials for specific bits of your project, setting up the navigation, or creating tooltips for example.
Google is great if you run into a specific problem, although Flash has been around so long you might want to stay away from the stuff from 2000 by entering whatever version of the software you’re using like “flash cs3 creating tooltips” would get you better results than “flash tooltips”.
If you don’t mind dropping just a little bit of cash, lynda.com is great as well.
Good luck with the portfolio.