Probably the most well-known Arabic news station is Aljazeera, from Qatar. Click on the yellow "Live broadcast" or "البث الحي" in the top left corner of the page to watch live streaming video. Or pick an article that looks interesting and read it. You can always use Google Translate to help you with the words you don't know.
The Arabic tends to be easier to understand on BBC than Aljazeera. You can listen to or watch direct BBC news in Arabic by clicking on the "تلفزيون مباشر" or "راديو مباشر" buttons located in the top left corner of the page. They also have a site for beginners to learn a little about different cultures and languages.
I've never used this as a news source before, but it is one American source that provides news in Arabic. I do not believe it offers a live feed option, but it does have some videos in Arabic.
Ahram - Pyramids
Here is a well-known Egyptian source for news, called "The Pyramids" or "الأهرام".