Sorry you're having problems. We just transitioned over yesterday and we're still working out some kinks, one of which is that files over 50mB are not indexing properly. This will be fixed later in the evening. Hang tight! I'd be happy to email you an older version of iTunes in the mean-time if you let me know which one you want.
This new design will allow our users to contribute more efficiently and it incorporates features which have been requested from us for the past few years, such as minimum system requirements and OS information. Give it some time!
In the mean-time, I am sorry for the problems you're currently experiencing with it.