Earl, as far as concentration goes, what I generally do is use headphones to block out most of the residual noise that may be distracting. Then, I would not think of it as a list of 30 songs that I have to prepare, but rather just the song that is in front of me now ...
As I am working on the different songs, I try to see if there are styles or parts of styles, or OTs that I could use in another song, just to shorten the work a bit.
You could also follow Gary's suggestion, which could help.