O'caml's HTML manual package is nice.  But Ocamlman may be even nicer.

Ocamlman is a specialized browser intended for Ocaml documentation. The
user has quick access to any part of the Ocaml reference manual.  The
menubar offers indices of table of contents, module indices, and
references to types, functions, exceptions, and modules.

Ocamlman is programmed with Objective Label 2.00.  Provided you have a
working set of olabl 2.00, installation is easy.

The URL of the source code package is:
ftp://ftp.is.titech.ac.jp/pub/lang/ocamlman200.tgz

Ken