Here are some explanations how to subscribe as vendor on the AT91 SAM Portal:
First of all, you need to register as an user. To do that, you just need to click on register on the home page and fill in the form, agree the terms and conditions and click on "SAVE".

When you are registered as an user, you then have to login and to click on My Profile. You shall come back to a form similar to the one you filled in when you registered, except there is a check box "Vendor: I want to become a privileged resource of Atmel Product" that you need to enable. Then, "SAVE" again and the next screen will be a Vendor-dedicated form where you can define contacts of your company, logo and other details.

Note that you will have to define the type of Vendor, but not the Type of Tools you offer. The Type of Tools you have defined or that you will define will be automatically reported in the Tools Type column. Up to 3 Types of Tools will be listed.

You won't be shown in the Vendor list immediately, but after the AT91 Portal WebMaster will have approved your subscription

Hope this helps.
AT91 SAM Portal WebMaster