IBOtoolbox has a great tool for SMS Marketing. It's simple to use and gains you access to look up an email for any mobile phone number you have.! The tool is located under Site Navigation - IBO Apps - SMS Lookup.
Enter in the mobile phone number in the box and click on "Look it up!" button.
Your results will render what provider that number uses, the SMS email address (to use for text message) and the MMS email address (to use for multimedia messages).
This information is coming directly from the provider's database giving you accurate information. Because of the sensitive nature of the data, your lookup results are not recorded inside IBOtoolbox. To use this tool, it costs 5 credits per lookup. If the number is not found for any reason, you will not be charged any credits.