Robby Workman has been putting some efforts to provide a bouncer site for Slackware that will redirects users to download Slackware to their closest mirror site. He has made the site open for public and it can be accessed on http://mirrors.slackware.com.
For some time, the one who maintained the getslack section or Slackware Mirror Administrator is out of reach and the mirror site hasn't been updated for some time. Hopefully this work can be solve that problem.
If you want to contribute by mirroring Slackware, please read the Mirroring Guideline.