Me, I turn them loose on the page.
Granted it's the outline's page nowadays but it's always been the page. Contemplating interviews with my characters invariably ends with them edging out the door to avoid this obvious lunatic with this silly "interviewing" business (except one Mongol-type raider on civilization from the steppes, whose reaction to the question of why he raids is "What a womanish question" -- and I don't know anything more about him).
Then, my inspirations tend to be incidents, not individuals. A brief flash of person, place, and plot, none of them complete. The work is building sufficient structure to hold it (or them, if inspirations stick together) in a coherent plot.
Time was that I had to build this entire structure to figure out who my characters were. They're a little more forthcoming nowadays, but still, if they're not running about in their native habitat, it doesn't come out.