Happens to me all the time. If I search for something and quit the app whilst on the search page it will crash every time I try to open iTunes back up. It eventually opens after about 5/6 attempts.
I had that for a day or two, but it suddenly stopped and hasn't come back since. When it was happening even a reset wasn't fixing the problem, it just refused to let me search for music. Wish I had better advice to give.
I had an issue where it constantly crashed on the search page. Kept trying to toggle back to it but it would still close out. My fix for this was making sure it was properly closed, signing out in Settings --> iTunes & app Store and then signing back in a minute after, and opening up the store again. No issues since then....
EDIT: Ha, scratch that. It is back! Doing the same seems to help again but it's quite inconvenient.