I'll elaborate a little more my problem, it sure can be interesting for other people. (Excuse my English).

The idea is to obtain with drupal commerce functionality similar to http://drupal.org/project/uc_member_pricing

Find valuable information here:
http://www.drupalcommerce.org/user-guide/product-pricing-rules-screencasts

Here we find different prices for role:
http://www.drupalcommerce.org/node/699

In summary, a product may have different prices according to the role of the registered user, but may also have a specific price for that product only.

One way I can think of would be to create a content type with three fields, "product referenced", "user referenced" and "Price". Create a rule to look for the referenced product and if it matches the registered user assigned to that product the specified price.

Would it be the right solution?
If so, how can we do with rules?
I'm still investigating.

Thanks and regards.

Has anyone found a solution to the problem that has arisen?

Thank you.

All Products insert with a price "0".

With imported feeds on a vocabulary (general rate) tariffs for each product with a field "rate number", "sku" and one for the "price" can be several different rates for the same product.

Imported with feed back on a vocabulary (individual price) another table with the fields "sku", "id user" and "price" for individual user.

The operation is as follows: If the product is within the vocabulary "individual price" and agrees with the registered user "user id" shows the price that has the vocabulary term "individual price". If not, look in the vocabulary "general rates", look in the "sku" match the "rate number" and that match the user fee and given the price.

How can do this with rules?

Thank you for your help.