Slackware is one of my favorite distributions for old computers. Unfortunately, it is not always easy to find packages for a given Slackware version. As the root must take care of dependencies in a Slackware system, I rarely like to install any new applications to a running Slackware. On the other hand, this certainly adds to the stability of the system.
So far I have used Linuxpackages.net for hunting obscure libraries or applications I have sometimes needed to use on my Slackware box or Slackware derivatives. No there is a new web based tool available: Slackfind.net (both in English and Russian). As Slackfind seems to find a lot of packages that are not yet available in Linuxpackages I will certainly bookmark this site to be used on my computers.