I've been a Rockne and ND fame since I was a kid.  I read a book on his life in grade school and became an instant admirer.  He was more than just a great coach and if you get the chance read a bio of him.  
I don't really collect Rockne items but my first major football card purchase was his 55 Topps All American card in the 70's for $5.   I also have one other item that will never leave my collection.  It's a piece from the crash.  My dad and I stumbled upon it at an auction.  It's a great reminder of that tragic day in Kansas when a great coach and man died.  
Here's a report on the accident.
http://www.irishlegends.com/Pages/re...lections5.html