Hope someone with shops setup experience can help with this. It may come a little unusual, but I need e-commerce solution where users access catalog and see products only after login. Which would require them to create a user account first.

It may look like an online version of offline club stores Costco or Samsclub, where users must first enroll/purchase membership to get access to discounted products.

Anyone knows which shopping cart can be setup this way? No matter whether it's an Open Source or commercial shopping cart.
I just need it to work this way. All help is appreciated.

My friend go to CRE LOaded peofessional b2b, users should sign in first to see products

www.magentocommerce.com
Theres a plugin on it (you need to download using connect) that will do that.

I believe Ubercart for Drupal can do this (haven't tried this feaure yet). You simply disallow cart access to all but one product for the anonymous role (Might need node access module for Drupal) and then once a customer signs up and pays the cart would switch their role and then they would see the rest of the catalog and pricing.