When practicing "the Tunisian" pay attention to your weight shift and link it to your hip movement. The speed for both the "Tunisian" and the Egyptian shimmy (remember, do NOT lock our your knees!) will come with time ^_~. When doing the flat figure 8, keep your hips flat from side to side, and avoid hyper extending your back by keeping your tailbone down and imagine a string pulling from your "above butt".
Here’s the article on my site with suggestions on where to get music to practice to, and what sort of CDs might make good starters. If you hear something you like in class I am always happy to write down the song and artist for you, too ^_^. Music is really important for bellydance, since it is the music made visible, as the drum solo by Mona below makes pretty clear.
On the topic of Practicing, Nadira Jamal of Boston has some great tips in her micro-articles "Do I Have to Practice" and "How to Practice When You Only Have 5 Minutes"
No matter how wild the dance gets, bellydance is always the music translated into movement. Nadia Jamal was a major player in the development of Lebanese style.
Here's Shahrzad, she is from the states, but has a career in Egypt now. This is her dancing to my all time favorite song. It's the intro to one of Om Kalthoom's classics, and an example of a song where parts have words, but you usually hear instrumental versions.