One of the burning questions for first-year students is "What music should I buy?" Way back when, before the internet and the plethora of magazines with music reviews, we used to buy music according to the album cover - a photo of a "real" belly dancer was a good clue that it would be "real" belly dance music. We were also in the situation of "beggars can't be choosers". But nowadays, there's SO MUCH music out there it's confusing if you don't know what you're looking for.
If you're just starting your music collection, ask your teacher what her favorites are or what she recommends for you in particular; or decide what dance style you're interested in and go from there. You can choose from American, Egyptian, Greek, Turkish, and Lebanese and all kinds of fusion styles.
Here are some recommendations in each category: Desert Knights, and Desert Wind (American); Jalilah's collection of Raks Sharki re-releases (Egyptian); Conchi's Belly dance Explosion (Greek); Sulukule (Turkish Rom); and Emad Sayyah's music (Lebanese). I feel these are most typical of each style and a good place to start developing your musical ear.
There are also many artists in each category whose music is more "accessible" (i.e., "Westernized") to beginning dance students, for instance: Raja, George Abdo, Eddie Kochak, Hossam Ramzy, Brothers of the Baladi, Sirocco, Omar Tekbilek and others. Just be aware that their music is often more suitable for fusion belly dance than authentic styles.
I learned long ago that Arabic music is considered standard ("generic", if you will) for Oriental Dance, and when in doubt, it's accepted more readily than anything else. I remember how confusing it was when I was backstage at a Greek restaurant getting ready for my first live band gig - and my dance friend Nadira told me the Greek band was actually playing Arabic songs....And the set they played for me also included music from "Lawrence of Arabia", and the Turkish 9/8 "Rompi Rompi" - my first clue to how complex the world of belly dance was going to be!