Mahmudur has developed a free extension for WP e-Commerce that enables default ‘Customer’ User Roles for store customers as well as Product Manager and Store Manager which gives limited access to Products/Categories/Tags and Sales respectively.
This Plugin allows Administrators using WP e-Commerce 3.8 to apply roles to their users. Currently the Plugin supports 3 default roles; Customer Role, Product Manager Role and Store Manager Role.
The Customer Role will be applied to anybody that buys something from your shop, they get no extra capabilities however their purchase history will display with all their account information on their profile page. This feature also makes it mush easier for the site admins to differentiate Customers from other WordPress users.
If other existing users purchase from your store (eg subscribers) then their user account will also be added to the customer count and the role applied.
The Product Manager Role will allow the user to edit and add new products, categories and variations. They won’t be able to see the sales logs or change any store settings.
The Store Manager Role will get full access to all WP-e-Commerce Plugin menus including store sales and store settings.