Is there any valid evidence regarding the “Q” document and supposed author Jesus? What are some good references for information regarding the historical Jesus?
“Supposed author?” Supposed by who? Nobody believes Jesus wrote anything.
Start here for info about the Q document.
There is the Gospel of Thomas, which appears to be a (purported) collection of Jesus’ sayings, but it doesn’t appear to be the Q document. It does at least show that sayings documents existed.
But otherwise, it’s based on analytical work of the documents, noting what shared items there are and aren’t and presuming from that that shared items are descended from a common source. If those shared items are all sayings, the it’s likely that the source is a list of sayings. If the shared items are biographical, then it’s likely that the source was a biography.
Right, except that that link goes to Part 1, and Q is discussed in Part 4.
Q wasn’t Jesus, just an alien with godlike powers.
As a member of Trekkian Orthodoxy Society (the Auld Kirk, as Scotty would say), I’d have to submit that Q is not canon. 
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Seriously, to partially repeat and partially expand on what Dex and Euty have to say in Part IV of the Staff Report on the Bible, Q is short for “Quelle”, the German word for “source.” (Germany’s equivalent to the Sears catalog is from a chain called “Quelle”. If you see a listing for a program on the “Q Source”, you should download it from your ISP provider across your LAN network and store it on your VCR recorder, then report it to the Department of Redundancy Department. :p)
It is a piece of what’s called the “Synoptic Problem.” It’s used to reference a hypothetical source or tradition, written or oral, that preserved many of Jesus’s teachings independently of Mark and was drawn on by both Luke and Matthew, who include in their Gospels a wide range of the same or very similar teachings, parables, and stories, but show Jesus telling/teaching them at quite different times in quite different circumstances. The evidence for Q is internal and logical to the modern Gospels, not anything known to history or to paleography: the First and Third Gospels do include many stories they share with each other but not with the Second, and do show them happening in radically different settings and sometimes for significantly different purposes.
The one bit of evidence we have is that the very early Christian writer Papias sys that Matthew made a collection of the logia (sayings, teachings, oracles) of Jesus “in the Hebrew language” (probably Aramaic rather than Hebrew proper, by then almost exclusively a scholarly and liturgical extinct language, in the same way as a casual reference to “He wrote in the Egyptian language” today would presumably mean the Egyptian dialect of Arabic, not the solely-liturgical Coptic).
The problem here is that the Gospel we know by the name Matthew is not a collection of logia but a polemic biographical narrative intended to convince the reader that Jesus is in fact the promised Messiah. And it shows every evidence of having been written in Greek, not translated from Aramaic or Hebrew. The solution may be if Matthew did in fact put together a collection of logia, of which Luke obtained a copy, then a later editor/redactor took Matthew’s collection of sayings and used Mark as a frame story on which to hang them, mostly categorized by topic into five long discourses, to produce what we have today by the name Matthew.