You can set customers as wholesale and retail using customer type.

One of the options - Wholesalers must sign in before seeing wholesale products.
You can modify product and category template to check if customer is wholesale, and if so to show all products otherwise show retail products.

Pricing:
I am working on a wholesale site ( www.sterlingforest.net ) and where they have
3 diff product types
per gram
per piece
net price


and 3 different customer types.
Gold
Silver
Bronze

Bases on any combination of those the page comes up with a price.

ex per gram and bronze - 75 cents a gram
per gram and silver 70 cents a gram
per gram and gold 65 cents a gram

price = weight * price per gram.



Let me know if you need more help.

For others that might be interested i created a demo for Edison.

goto http://www.sterlingforest.net

and use a demo search page: http://www.sterlingforest.net/Search2.aspx

search for a product "Wholesale" It wont sow up on above page
Now login as wholesaleuser password: wholesaleuser
and do the search again and it will show up.


Also while not signed in click on category: Retail/Wholesale the item wont show, but if you sign in with above user, you will see it when you go the the category.