Remove space from those two links after http!!
First add this to your /etc/slapt-get/slapt-getrc
Save the fileCode:SOURCE=http ://darkstar.ist.utl.pt/slackware/addon/slacky/slackware-12.0
Then at console run
After it's updated, runCode:slapt-get --update
That should do it. If yours slapt-get is broken (update failed) then go here and look seventh post.Code:slapt-get --install gpsd