At last - Artist O and Song 15. In fact I had the answer months ago, but thought it was wrong.
It's
The Corvair Song by the Joe Parr Band.
If you Google "Corvair song" it comes up in the first few hits, on either web or image searches, but I just couldn't match any photographs I could find of the Joe Parr Band (and there aren't many) with any of the artist pictures in the puzzle, so I rejected it as a possibility.
Then I eventually came back to the clues. I recognised the first guy, but couldn't remember who he was. I didn't know the second, but from the cards he's holding I guessed he might be a quiz show host. In fact he wasn't, but a Google image search on "quiz show host" did find him, albeit on page 42, with images restricted to black and white only.
The name Jack Paar made me think back to the Joe Parr Band, then in one of those
moments I remembered who it was in the first clue. We get extensive (if not excessive) coverage of US Presidential election campaigns in the UK, and Mr Wurzelbacher, aka "Joe the Plumber" was no stranger to our screens in 2008.
So Joe Parr looked like the answer after all, but I still couldn't square it with the photo. I found that Joe Parr has some photo albums online - 49 of them in fact. I'd skimmed a few, but they are mostly friends and family, and to an outsider, I'm afraid they are excruciatingly boring. But this afternoon I decided to go through them methodically, and luckily I only had to look through the first eleven before the puzzle picture came up.
I'm not sure that it's the standard line-up of the band, but at least Joe Parr is in it (he's the one with the saxophone), and I can at last offer the answer with some degree of confidence.