lsmod man page — description and explanation of its output.

insmod man page — description and list of command line options.

modprobe man page — description and list of command line options.

rmmod man page — description and list of command line options.

modinfo man page — description and list of command line options.

/usr/share/doc/kernel-doc-<version>/Documentation/kbuild/modules.txt — how to compile and use kernel modules. Note you must have the kernel-doc package installed to read this file.