Reading is the best way to improve your French comprehension and vocabulary. I’m sure you already read the paper or watch the news in English. Why not get the French perspective as well? French newspapers are overtly political. In other words, they don’t hide their bias. I like to take a top story and look at it in each of the three top papers online:
You can access these official sources of French news for free online. If you get in the habit of looking at the paper, your vocabulary will improve and you will expand your view beyond the American perspective.
Of course, the ever-changing blogosphere is a great source of unofficial commentary. I’ll leave you to explore that on your own.
Current French movies are a great source of living culture. You will learn words you wouldn’t learn in a typical textbook (some that you shouldn’t learn) and will get a feeling for another aesthetic outside Hollywood. You may want to research over the Internet in order to pre-screen for content that might offend you. The Internet Movie Database(http://www.imdb.com/) is a great resource on film.
French-language comics and graphic novels have a huge following. They range from the classic and the quaint (Astérix and Tintin, for example) to the surreal and the shocking.
To acquire books, music (another great way to learn new words), and movies you can check online. Amazon(http://www.amazon.fr/), for example, has a French site.
You’ll pay for shipping, so buying more at once is a good idea. If you buy movies, watch out for region coding and format. Most American DVD players are Region 1 only and NTSC only. You can get region-free players if you look for them.