What are the chances...

of some guy way up their in the music business, coming to your gig, likes you, and wants to speak to you about a once in a lifetime chance at a recording contract?

You mean as in lucky break?
Take a good hard look at the big acts today. They got where they are through marketing.

If you're trying to get there through talent alone. . .
Buy lottery tickets, your odds are better.

I think this sounds abit cheap but how does marketing work?

Before somebody can book you/sign you/join your fan club/whatever a couple things need to happen:

1. They need to know about you. The odds that some A&R guy is going to wander into a bar to hear music are good. The odds that the A&R guy is going to wander into a bar where he's never heard of the performer are close to zero. He may go hear live music 5-7 nights a week - but he's got a long list of bands where people have said "this one's fantastic - you've got to check them out". That's what's on his dance card.

So the only way you're gonna get heard is to either be the one people are talking about, or to be opening for the act people are talking about. The first one is marketing... the second one is pure chance.

2. They have to not hate you before they've heard you play. Ever wonder why so many bands on the radio sound the same? Why 90% of the band promo shots you've seen include a pose in front of a brick wall? Why everybody in certain styles of music seems to wear the same tattoos, or the same hair style? Why so many bands in bars seem to shop at business casual stores?

They're playing it safe. The A&R guy will tell the magazine interviewer that he's always on the lookout for a new sound, something different. What he's not saying is that he's looking for a new sound that's already selling records on their own, or for a smaller label. If he can't find that, the next safest bet is somebody that sounds like someone selling records.

So if you're a total unknown, marketing works by telling people you're a lot like brand x. If you're not a total unknown, but you're not really known yet, marketing works by telling people that other folks like your music (and proving it with reviews, sales figures, etc.)