My only dealings have been during through the mail or later, on ebay. Some of the names I recognized from publications or articles on cards or the annual price guides as contributors. My only ventures outside of small local card shops/shows and mail order/ebay would be to pop into a card shop during my travels (family vacations, US Navy). I have never been to what most would consider a large show, like a National, and the Pacific NW doesn't really seem to be a major hub for sports cards compared to many other places, although there is a long standing card club...WSSCA, of which I am not a member.
http://www.wssca.net/
Not sure who might really be considered hobby legends though. To me, these were people selling cards. I remember buying quite frequently from TCMA and Renata Galasso through the mail in the early/mid 80s. Hall's Nostalgia and The Collector's Den stand out too, as does Card Collectors Co. I somehow got on tmany of their mailing lists for a time, maybe through Baseball Digest ads or some other means. I lived in the Seattle area, so I got catalogs from Michael Cramer's shop and visited it occasionally, before he grew into Pacific Trading Cards. Paul Marchent, BA Murray, Wayne's Shoebox, Kit Young, Bill Henderson, Stan Martucci, etc. are all names I know I bought cards from through the mail too from ads they placed.
I bought a few neat items from Ted Taylor on ebay, who was at one time a Fleet Executive. Got some neat Fleer proof/prototype items and some tougher Brooklyn Dodger autos.