Once, I was at a karaoke bar. This is one of my regular haunts, so I felt fairly at home, and of course I'm a decent singer as well. I guess one of the patrons caught on to my aura of confidence, because she came up to me and asked how to request a song. Fine, I thought, I'm a nice Minnesotan boy, I'll help her out. So, I explained the hand-delivered slip request system, asked her to verify that her song request was in the book first, and explained that this KJ didn't take tips, and she zoomed off to request a song.
Well, about five minutes later one of her friends comes over to ask me the same bloody question. And another, about ten minutes afterwards.
The patrons at a karaoke bar might be happy to help you, sure. But that's not their job. The KJ is the person organizing and coordinating the event, and they should be the one to explain the rules, keep order, and generally ensure everyone is having a great time. So if the KJ is busy, maybe ask where he is, but there's no need to ask your fellow patrons for help.