Q: Quick question on Apple IDs

I have all my Apple products (Macbook Pro, iPad and iPhone) registered to an @me.com Apple ID. Having gotten divorced, I no longer want to use that account, however I realize since it's an Apple email, I can't change it. I've decided to proceed by creating a new Apple ID and associating it to all devices. Is there a way to find out if I will need to re-purchase iPhoto, iMovie, GarageBand for my Macbook Pro? Or, since they were pre-loaded onto the laptop when I purchased it, will they stay in tact? Aside from having to re-purchase any other apps, music, etc. previously purchased with my old Apple ID, are there any other items I should be aware of prior to making the change?