Then there's The Book of Enoch- a wearisomely repetitive apocalyptic text- featuring rebel angels, nephilim, visions of heaven and hell and some primitive cosmology. Christian interest centres on the appearance of a Messianic figure called the Son of Man. Is this where Jesus got his title from? Possibly. But, then again the portion of Enoch that deals with the Son of Man was written in the Christian era and some scholars- admittedly not the majority- regard it as a Christian text.
Finally, the Pirkei Avot- the section of the Talmud that contains Hillel's version of the golden rule: it has many echoes of gospel language and gospel themes, but no other texts that directly parallel the words of Jesus. It's a collection of wise and witty sayings from the world of the New Testament- but its atmosphere- safe, conservative and beardy- is very different. Again- though these rabbinic sayings may have been floating around in the oral tradition for ages- and probably were- they weren't actually written down until the 2nd century- which means our record of Jesus's version of the golden rule predates Hillel's.
If the sayings of Jesus were plagiarised from other sources I've yet to find the evidence, but I'll keep on looking.