Hi,

After you receive the email confirmation that the billing service is turned on for your subscription, visit the subscription page in the account portal. Click the subscription you want to monitor, and then click alerts as per this link:

http://azure.microsoft.com/en-in/documentation/articles/azure-billing-set-up-alerts/

If you have already done it and still if you are unable to see alerts, then I would request you to contact Billing support, it's free, and it's the best choice for you.
Please contact support team by creating a support ticket at:
http://www.windowsazure.com/en-us/support/contact/

They will be able to help you with this request.

Hope this helps.

Regards,
Azam Khan

Hallo! I have alrady done it. Here what answer me billing support: 

Thank you for the response.

Your question appears to be a involving a preview feature instead ofbilling and support as selected. 

Please note that during the preview phase, support is provided via the forums. 

To obtain support please go to the following link for assistance: http://www.windowsazure.com/en-us/support/preview-support/ 

At the time of General Availability our technical support options will change and we will update the support portal with updated support options. 

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