Secondly, I really don't know where this Greek is from. If I get a hit from Euthyphro, that tells me naught all (without spending more time than I have researching who this Greek dude is). Is this 7th Century BC Greek or 1st Century? Is there a list of Koine Greek collections so that I could narrow my search and only see Koine hits?
I am encouraged by the desire for accuracy to the Koine period that this frustration represents. Be encouraged!
I will offer 3 things: 1) A master list for ancient texts
, in alphabetical order, which aims to provide 2 main pieces of information about each text: 1) date of original composition. 2) language of original composition. https://docs.google.com/open?id=0B-eeaU ... G5ZTWFIZXM
Pared down from this master list... 2) A select list of Koine Period texts that were written originally in Koine
, and apparently are extant in Koine in significant portions https://docs.google.com/open?id=0B-eeaU ... jNFSnBOWGM
I then made a list of which of these select texts were cited most often by BDAG in his lexicon. I will not send you that, out of a desire to not overload you. But based on that and other factors, I compiled a list of "favorites" links to the some of the more helpful texts for finding citations. This was for use in internet explorer's browser. 3) A folder of shortcuts (URLs) to the koine-original, koine era texts that I've found most helpful for finding citations of usage, in order of their helpfulness, and nearly all including a side-by-side shortcut to a corresponding English translation https://docs.google.com/folder/d/0B-eea ... JlNHc/edit
In actual usage, so as not to overload you, perhaps I could offer this statement on my actual usage of the above resources.
I use #1, the master list, when I have found a good citation on Perseus and want to check if it is usable. So I just open up this list and do a CONTROL + "F" search for the author.
I don't often use #2. Though I found it helpful in making #3.
And I use #3, the shortcuts, when I have a particular reference that I want to look up. For instance, maybe I'm looking up a verb in BDAG's lexicon and it cites 3 Macc 2:21. With a click of the button (on the relevent shortcuts), I can have both the Greek and an English translation in front of me in seconds. But, as I said, mostly I use that when I have particular references I want to look up. If found desireable, you could set up the same list of "favorites" (Internet Explorer) or "bookmarks" (Mozilla) using these URLs.
All the best in your efforts!