Finding stuff on networks used always to be difficult, but in recent years, search engines have become amazingly good at digging out unconsidered trifles from the myriad items of information available on the net. However, for the (La)TeX user, confusion is added by the tendency to index the same file at several CTAN mirror sites.
Further, the (La)TeX user usually needs the most recent version of a package; it’s a rare search result that describes itself as obsolete!
The CTAN catalogue, several years after it was introduced, has developed into a powerful tool for dealing with these difficulties. It provides an entry for each package to be found on CTAN; users may search the catalogue for an entry, or they may browse its contents, using the catalogue’s lists of “categories” of item.
The basis of the catalogue is a collection of small, stylised, articles; each shows basic information about a package on CTAN, and includes pointers to download address (on a CTAN mirror), documentation and home page if any, and related packages.
The CTAN central database machine offers a “Browse CTAN” area, with links to the list of packages, to a list of ‘topics’ (with packages that match each topic), and to a list of authors (with their packages).
In addition, every CTAN mirror holds a copy of the catalogue, presented as a series of web pages; one may scan the files in alphabetic order, or use a category-based index. Such access is not as “sophisticated” as that on the central site, but it served for years before the central site appeared.
This answer last edited: 2014-03-17