Have you tried the Wood County Library? The genealogy/history section in that library is extremely good. I suspect that you might find additional information on him in the History of Wood County in the Civil War by Matheny. He also might have a bio in the books written by John House. House was a man who was diagnosed with a heart condition in 1905, so decided to spend the remainder of his life just writing down the history of the area. He would interview people, do document searches, etc. He actually lived into the 1930's. He has extensive documentation of various histories in the region that is many thousands of pages long. He had a few typewritten books that have been bound and given to the Wood County Library and some to the Jackson County Library. The books were never published, but people have started to scan the contents in and post on the internet as the books are now public domain. Even if the staff there does not have time to help you, they can put you in touch with local researchers.

Blair has a historical marker located on the grounds of the Oil and Gas Museum in Parkersburg. You might contact them to see if they have any information. I don't recall any major connection between Blair and the oil industry beyond what any Parkersburg politician would have had in 1860-65, but they would certainly know more. It entirely possible that this marker was set there due to other unrelated connections to Blair. The corner it is located was very central to Parkersburg in the 1860's.

I see Blair is buried in Salt Lake. So, I am guessing you are there also. I believe that the Mormon library there has a copy of Matheny's book. You might also check Hardesty's Biographical Atlas of Wood County, WV 1882. The West Augusta Historical society has also published a series of books on various counties with oral traditions of various families. You might ask if anyone of the Blair family contributed anything. There are still plenty of the Blair family living in Parkersburg and the area around it.

I do not know of a specific biography for Blair, but I can check my copy of Matheny when I get home and verify that information.

His time on the Wyoming Court circuit was certainly colorful. Here's an account of a trial where Blair was presiding as detailed by a lawyer named AC Campbell and appears in the Annals of Wyoming 1947:

Judge Blair was presiding over some murder case when a gunsmith was called to the witness stand to give expert testimony on the murder weapon. The man sat on the stand holding the defendant’s revolver when the judge leaned over to that side to spit a mouthful of tobacco into a spittoon on the floor. When he did, he noticed the gun was pointed right at him.

“Mr. Witness, is that gun loaded?” Blair asked.

“Why, yes, your honor, it is,” the gunsmith/witness replied.

“I’ll ask you then to kindly point it toward the lawyers. Good judges are scarce.”

A little bit about Blair's time in Wyoming can be found in "Exiling a Wyoming Judge" by T Alfred Larson. https://scholarship.law.uwyo.edu/cgi/viewcontent.cgi?article=1403&context=wlj

Blair is not the subject of that article.