If you want to do PR another good resource to check into, especially for internships, are management companies (both personal and business). I had interned with one in LA many moons ago as I was not 100% sure which direction I wanted to go in the industry and it was a great place to learn that part of it. My job was to call radio stations, especially college ones who reported their charts, to convince them to play our clients who were either baby bands or still trying to get signed. It was the perfect place to really see how the PR machine works.
Another source to check for internships, which is really how you get your toe, not your foot in the door but you gotta start somewhere, is Radio and Records
http://www.radioandrecords.com/ , CMJ
http://www.cmj.com/ ; Billboard
http://www.billboard.com/bb/index.jsp and if anything these are also great resources to see what type of PR is being done and how its being done. The best thing for you to do is read everything and anything you can and then come up with your own ideas on how you would do it different. Attend any sort of music conferences you can find like SXSW, CMJ has a really great conference there in NY. These are perfect places to network. Always remember when networking with these people is to be very respectful but forceful and be well informed (do your homework). Don't come off as being a fan, etc. (I've seen this a million times does not work). Anyone can pretty much BS their way into something but then you need to be able to back it up with your brilliance. Its a tough ass business and if you do it right you will be successful but do it wrong and it will chew you up and spit you out so fast...its brutal.
Here's another good resource site Artist Pro
http://www.artistpro.com/ . I've used their Artist Resource Books for years. It has all the listings of majors, minors, and indie labels, management, magazines, etc. Also pick up the Daily Variety and Hollywood Reporter and look in their employment sections.
