Little is known about Euclid’s actual life. He was living in Alexandria about 300 B.C.E. based on a passage in Proclus' Commentary on the First Book of Euclid's Elements. Indeed, much of what is known or conjectured is based on what Proclus says. After mentioning two students of Plato, Proclus writes
There are a few other historical comments about Euclid. The most important being Pappus' (fourth century C.E.) comment that Apollonius (third century B.C.E.) studied "with the students of Euclid at Alexandria."
Thus, we know almost nothing about Euclid’s life. But we have more of his writings than any other ancient mathematician. Besides the Elements, there are the Data, On Divisions of Figures, the Phaenomena, and the Optics. All are included in the Euclidis opera omnia of Heiberg and Menge (see below) in Greek and translated into Latin. Other translations are listed below. Euclid also wrote other books which no longer exist but were mentioned by later writers. They include Surface Loci, Porisms, Conics, and the Pseudaria (that is, the Book of Fallacies).
The text of Heath's translation of Euclid’s Elements is also available on-line at the Perseus Project at Tuft's University starting with the first definition of book I.