Abebooks.net has a great post in their Rare Book room called Clues on Collecting Sherlock Holmes (thanks to Mark Wardecker for the link).
Naturally, they had to give a nod to the giant in the field of collecting Sherlockiana, John Bennett Shaw:
It is doubtful that anyone will ever again approach the sheer size of the collection amassed by the late John Bennett Shaw. Like Professor Moriarty, Shaw sat at the center of a vast web whose vibrations seemed to sense the appearance of anything new in the Sherlockian firmament. Shaw had his minions everywhere, and very little escaped him. But times change. The Sherlockian world has grown to such gigantic proportions that no one collector will ever again so dominate the field.When I started collecting as a college student, I thought I had amassed quite a collection of Sherlock Holmes material when I filled a single row on a bookshelf. Now, I've got three bookcases overflowing, plus at least 5 large boxes of books that don't yet have a home. And there are plenty of books that I don't buy.
Those who knew JBS personally remember a gregarious and generous man - generous with his time and with his collection. The fact that Shaw's collection was the basis for the Sherlock Holmes Collection at the University of Minnesota Libraries certainly proves that.
Personally, I never had the chance to meet Mr. Shaw. If there are any readers out there with a personal experience with the great Sherlockian collector John Bennett Shaw, a comment would be welcome.