Seems the routes I've seen are word of mouth, flyers around a training center, and private group message board recommendations. At my airline at least, the 401k is through Fidelity that provides advisement services after a certain portfolio threshold (400k) and Schwab advisors through the union. I've also seen sponsoring union events, airshows, social media advertising, but I can't speak to the effectiveness or price of that.
Also the desires of each person are different. I don't really want a lot of investment advice, more just maximizing my company contributions and being smart about taxes. Some folks want the full monty advisor with the associated costs.
That makes sense - we custody through both Fidelity and Schwab and see a lot of airline rollovers coming from those entities.
Word of mouth is definitely what we have experienced up until now, but I didn't know if you guys see firms showing up to conferences or advertising in industry publications (and if they are, is it even effective?).