Great advisors are driven by 3 primary variables: the industry/sector of your product, your existing network, and where you are physically located.
Industry - Your industry may or may not be network driven, in the sense that industry members regularly come together organically (venture capital) or stay relatively separate (accountants). If they regularly come together, industry events are great ways to building your network and eventually finding advisors. If they do not, this is where the value of your network comes into play.
Network - Your network is the first place to start, going first through 1st degree connections and then to 2nd degree connections. 2nd degree connections can ultimately be more helpful as the individual has less of a personal relationship with you and may be more amenable to a business relationship that is more objective than your close friends could ever provide.
Physical Location - While this may be difficult to permanently change, your location matters, and your proximity to the circles you care about matters. If you are not already in the center of where you want to be, it may be worth a trip to where the highest number of potential targets are if you can stack enough meetings together.
Happy to further expand on a call if you'd like.