Slackware is not like Ubuntu in many ways. You will need to do some reading and learning to get the wireless working in Slackware. The good news is, if it worked in Ubuntu, it will work in Slackware.
This link is the best document I have found on this topic. It works, if you follow it, and have a few skills.
The link -->http://alien.slackbook.org/dokuwiki/...ckware:network
I don't know how much you know about Slackware, if you need help installing packages, go to this link;
There is help here to install, configure and manage your shiny new Slackware system. This is how I got stared, it works.