No one knows for sure where it originated. On the other hand, no one knows for sure where any of the canonical gospels originated either.
Aurelio de Santos Otero has written: 'Das kirchenslavische Evangelium des Thomas' -- subject(s): Criticism, interpretation, Gospel of Thomas (Infancy Gospel)
Margaretha Lelyveld has written: 'Les logia de la vie dans l'Evangile selon Thomas' -- subject(s): Gospel of Thomas (Coptic Gospel), Redaction Criticism
Thomas Wearing has written: 'The world-view of the fourth Gospel' -- subject(s): Bible, Criticism, interpretation
Stephen J. Patterson has written: 'Beyond the Passion' 'The fifth gospel' -- subject(s): Criticism, interpretation, Nag Hammadi codices, Gospel of Thomas (Coptic Gospel)
Thomas L. Mellen has written: 'Woman's place under the gospel' -- subject(s): Women and religion, Women in Christianity
Thomas Menamparampil has written: 'Cultures in the context of sharing the gospel' -- subject(s): Christianity and culture, Cultural awareness, Evangelistic work
Basic information on the Gospel of Thomas can be found on Wikipedia. There is also a website devoted to the Gospel of Thomas. The library is also a great place for research on the gospel.
The gospel of St. Thomas is not an authorized book of the Holy Bible and is not included as such. It was not written by the apostle Thomas. I would not put any credence in its contents. Incorrect. It is the only Gospel that is available today in it's original form. It is one of the most important Christian documents available today.
Risto Uro has written: 'Thomas' -- subject(s): Bible, Criticism, interpretation, Gospel of Thomas (Coptic Gospel) 'Sheep among the wolves' -- subject(s): Bible, Criticism, interpretation, Q hypothesis (Synoptics criticism), Sending of the twelve
Jacobus van Amersfoort has written: 'Het Evangelie van Thomas en de Pseudo-Clementinen' -- subject(s): Criticism, interpretation, Gospel of Thomas (Coptic Gospel), Homilies (Pseudo-Clementine), Recognitions (Pseudo-Clementine)
Jean-Marie Paupert has written: 'The politics of the Gospel' -- subject(s): Christianity and politics 'Thomas'
The Gospel of Thomas is not recognized as scripture by most Christain denomiations.