It's also one of the few AI books that isn't rooted squarely in Algol. It's written with fairly decent though not always portable Common Lisp, just like most Common Lisp books of the era.
It can be read here, in mobi or zipped HTML format: https://github.com/norvig/paip-lisp/releases/tag/1.1
Or here, in PDF: https://github.com/norvig/paip-lisp/releases/tag/v1.0
For a native web copy, abuse Safari Online's free trial. It's what I assume everyone else does when they want to read a niche technical book that O'Reilly put out but doesn't print another run of.
Depending on the day, the book ranges anywhere from $2 to $60 on Amazon, used, if you want a hard copy.
(Edited to fix the very butchered title that I wrote in error initially.)