BETWEENYOUANDME, I liked this puzzle quite a bit. I LOL'd several times while solving it. My favorite clue/answer pair might be 20A. Ones with good poker faces? (RHINOS). Ha! I'm laughing again.
There were a number of other fun and funny clue/answer pairs:
69A. Result of hitting the bar? (SPACE)
28A. Student saver (BELL)
16D. Offensive poster (TROLL)
42D. Setting for a watch? (MOVIENIGHT)
63D. What the pros say (AYE)
97D. Too big for one's britches, say? (OBESE)
But, I suppose I should back up a little and say that I enjoyed the theme. The 'Word Search' of the title was nicely executed. If you go looking for "building" or "hours," where do you find them? POSTOFFICE. HARHAR - except seriously.
Of course, it's not just word play I enjoy in a puzzle. There was plenty of straight-up appealing vocabulary in this grid like TAINT, UNLEASHED, OCCULT, and my favorite, NICETY. You don't see that word every day. I was thinking our friend and fellow solver Huygens might enjoy 52A. Like Fermat's last theorem, eventually (PROVEN). I wondered also if he would be adding PAEANS and MAXIMS to the puzzle he imagines creating that will contain only unnecessary or odd plurals.
In among the gems, there were a few odd balls, including 119A. Back entrance (POSTERN), which I thought was cray cray, but when I looked it up, I found that it is a completely normal way to refer to a secondary door or back gate to a fort or castle. And I thought the clue for 13D. (JAWBONE) was a little weird. Chin former. Hunh. But maybe that's just me.
Despite my enjoyment of the puzzle as a whole, I am giving the 1A. answer a C. I'm not a big fan of your "quote" clues to begin with, and neither "Shucks" nor AWNUTS really sings.
As chance would have it, I finished the puzzle in the south west region. I didn't immediately figure out the totally excellent clue 100A. Flames that have gone out? (EXES- ha!), so I looked at the nearby 90D. Red ___, a three-letter answer in which I had already placed the "O" of AHEADOFTIME, and thought to myself, hmmm, I wonder what that's going to be. I couldn't guess, so I went back to 100A. and figured it out. Turns out the answer to 90A was Red SOX. Go team!