A Deep Well
It's rather a shame that, given his prodigious body of work, the only thing that's going to be mentioned beyond a nod and a wink is I Am Legend.
Ah, I remember the summer of 1990, Vancouver, on a mission to locate a copy of said novella (it is on the short side). Not in print at the time, no copies to be found among the plethora of used and antiquarian dealers in the GVRD, but... the library system had a single, somewhat dog-eared, hard bound first edition on regular loan and (and!) it was located at the closest branch to my house (Fraser Street). Of course it was "in". I borrowed it, read it, enjoyed it, appreciated the differences with the Price film and the Hollywood "adaptation" that was Omega Man, and returned it. Three years later I went back to re-read it but it had disappeared. Swiped. Of course. These days I suppose they're abundant, but the thrill is gone.
Oh, and The Last Man on Earth (Price) is in the Public Domain. So you can legally acquire it via those means usually reserved for the acquisition of that which is illegally obtained, if you take my meaning. Also, the Internet Archive have a not so good print for download.