You can visit Weller's site HERE and read some of his out-of-print books including Science Made Stupid that won the 1986 World Science Fiction Society's Hugo award for Best non-Fiction Book.
Weller was the artist for many of the early Fahey covers. Weller had his psychedelic phase and then his wood cut phase. I prefer the wood cut covers. He also designed that Takoma "T" logo with the arrows.