I, too, have finally crossed that line. Having run out of HPL stories, I've started reading his mail.

Two volumes of correspondence between Lovecraft and Robert E. Howard, from 1930 to '36, and boy golly jeepers is it ever racist. HPL has written some awful things, as we all know, but REH could give him a run for his money. It's actually kind of fascinating to watch the two strands of racism interact: the blue-collar "redneck racism" of Howard and the pseudo-intellectual "country club racism" of Lovecraft.
I know Lovecraft's racism is a worn topic, but, since Howard and Lovecraft's correspondence started over Lovecraft's mistake in "The Rats in the Walls" concerning the waves of invasion of the British isles, the topics of the early letters are all about archaeology, anthropology, heredity, and the racial theories of the day, so you can see where this is going. The word "Aryan" gets thrown around a lot, and both men are pretty casual about dropping the N-bomb.
All that aside, I've already hit on a gem that justified the purchase price: the criminal past of Lovecraft's own family tree!
The Casey house in Kingston burned down in 1763, reducing its occupant (my great-great-great-grand-uncle Samuel Casey) to a relative poverty which drove him into crime--the rather common and winked-at crime of counterfeiting. He had been an accomplished silversmith in addition to his agriculture, (specimens of his work are in both the Boston Museum of Fine Arts and the Metropolitan Museum in N.Y.) and he now--alas--turned toward the manufacture of Portugese moidores and Spanish milled dollars--abetted by all his respectable neighbours! In 1774 the long arm of the law nabbed him, and he was sentenced to be hanged--but one night a party of planters blacked up as negroes stormed His Majesty's Gaol at Little-Rest Village (now Kingston Village) and liberated the culprit; so that he rode out of Rhode Island annals toward the west on a white horse in the dark small hours, with coat-tails flapping behind him! Other Casey descendants have proved more law-abiding...