Migration Assistant Only Copies User Data

Just got a new MBP, updating from a 4 year old white MB.

Forgetting how the migration from my gumdrop iMac to the previously mentioned MB went 4 years ago, I blindly accepted to transfer all data from my Time Machine external drive to the new MBP.

Unfortunately, all the data seems to be on the new MBP but under the previous MB's user name. I forgot that this is how Apple does things and it's irritaing. So, I now have a shiny new user that I started today and a mess old user that has all my data.

I am unable to transfer photos, music or anything from one user to the other. When I choose to import photos to the new iPhoto, I find the old user's Photos with a red and white locked icon on it.

How do I share documents between the old and new user? Basically, I would be pleased with only putting music and photos on the new user and leaving the mess on the old user.

Any advice would be appreciated.