The TOEFL® test measures the ability of non-native English speakers to communicate in English, as it's read, written, heard, and spoken in an academic setting. The test is accepted by many English-speaking academic and professional institutions.
Official TOEFL Website Includes information about how to sign up for the TOEFL test.
Complete Guide to TOEFL Test by 
Pass Key to the TOEFL iBT by 
Essential Words for the TOEFL by 
Cambridge Preparation for the TOEFL® Test by 
The Official Guide to the TOEFL Test with DVD-ROM by 
Writing for the TOEFL IBT by 
500 Words, Phrases, Idioms for the TOEFL IBT Plus Typing Strategies by 
