Buddy Babylon, by Scott Thompson and Paul Bellini. It'll never win an literary award, but it's a fun and silly read: the "autobiography" of Scott's best-loved stand-up persona, Buddy Cole, familiar to all "Kids in the Hall" fans. Co-author Paul Bellini was one of the KITH writers and made frequent cameo appearances wearing only a towel.
Puckoon, by the late, lamented Spike Milligan. Spike was THE god of comedy worshipped by the Pythons and many other British comedians; he was the creator and co-star of BBC Radio's "Goon Show" (which launched the career of Peter Sellers). "Puckoon" was Spike's only novel and shares much of the quirkiness of his radio and TV work ... I've just discovered that a film version has finally been made ... another one for the essential viewing list!
The Dorbott of Vacuo by Patrick Woodroffe (sorry, couldn't find any decent links to the book by itself, but there's a booklist in the artist's site). Woodroffe is better known for his art than his writing, but this tale of a world where the laws of physics are somewhat ... flexible (deranged might be a better term) ... should be grabbed if you ever spot it.