It wasn't all globetrotting horror. Herber's Return to Dunwich revisited Lovecraft's questionable town and provided unpalatable answers, in one of the two or three best books ever written for the game. In that book, Herber took his place with Ramsey Campbell as a chronicler of the human half of the Mythos; it's a paean to despair more immediate than some purists' disdainful "cosmicism" would allow. (And it has giant monsters in it.)
Doc also helped design "Raid on Innsmouth," one of the most revolutionary scenarios ever for any game; and his "Haunted House" is a dungeon crawl to make the saints weep. He wrote the first Clanbook: Tremere, which is considerably better than you'd expect, even if you were expecting something by Keith Herber.
He left game writing for years, fed up with the myriad miseries attendant on it. And then he got back in, starting Miskatonic River Press to publish Mythos-related books and games.
A little while ago, he sent me review copies of his two latest books. Full reviews of both remain forthcoming, but I can tell you that if you play Call of Cthulhu you won't regret going ahead without me and getting New Tales of the Miskatonic Valley. Doc contributed one of the six scenarios there, set in "Foxfield."
And even if you don't play, do pick up his newly re-issued Dead But Dreaming, an anthology of Mythos fiction edited by Keith Herber and Kevin A. Ross. It's among the best Mythos anthologies ever published; it's almost certainly the best one of the decade. Adam Niswander and Ramsey Campbell are only the highlight names.
But the name that means the most, the guarantee of quality, of actually caring what goes between the covers -- that name is "Keith Herber."