The Diamond Sutra, along with The Heart Sutra, are among the most popular works of the Prajnaparamita group of Sutras. Indeed they are among the most popular Sutras within the Mahayana cannon as a whole.  This translation has been prepared by the Buddhist Text Translation Society of the Sino-American Buddhist Association, under the auspices of Gold Mountain Dhyàna Monastery in San Francisco. Download the Diamond Sutra here in full length (264 illustrated pages):

The Diamond Sutra

Dhyana Master Hsüan Hua – The Shurangama Mantra