Or are they all equal? I am a musician, so this is my main concern with my upcoming tablet purchase!
I can't really see many people spending $600+ for itunes to work so just in case you wanted another option the G Tab is a fantastic android tablet, but Frank is correct in saying you cannot legitimately use iTunes on anything other than an apple device so ifs your true concern for music then sure, maybe grab an iPad, otherwise you have plenty of options that from what I have should have an roughly the same stereo audio available.
This would be my preference because of everything that I currently run. I love iTunes so I have a huge library of music, books, movies, video, photos, etc. Of course I love the 10 inch screen, although it's not necessary for music purposes. Bonus, I can stream my music and movies or other media thanks to the home sharing option. You can also download the Garage Band app for less than $5 and create music of your own. It's a great tablet.
If music is your major concern then I would recommend the Kindle Fire it is $200 and uses Amazon's Cloud service to store your music. Though if you already have a large iTune's library then you will want to get an iPad as its the only device that will work with iTunes.
I think ipad 2 would be the best one for you, Candice. The reason is, Androids don't really do iTunes too well. You can sync itunes with an android, but it does require a third party app to do so. You probably have your music library on iTunes, so you should probably go a route that will enable easy access to all that content. Also, I heard you can't watch iTunes movies on Android devices... don't know if that is of any concern to you though.
If iTunes is not what you use, you could consider HP's touchpad tablet. It has some features geared at music lovers, including Dr. Dre's Beats Audio, which may be of interest to you.