All CTAN archives support index searching, and can archive, compress and send entire directories with a single command. The best method is via the CTAN web site . It provides all the functions of command line ftp, with an interface that annotates most directory names with a description of their contents. Unfortunately, the web site is in America and response time is poor. A compromise is to browse the Australian site with mosaic, but that doesn't provide the annotations.
More information is available on unpacking and installing packages.
The organisation of CTAN archives is described below. Most packages described in the LaTeX Companion are not kept in the LaTeX2e macro directories.