Apps :: Installing new apps after fresh install

NOob ALRET!

Hey all. I just did a HD install of DSL 0.5 with no probs.
However I don't know how to install programs.  

What do I do with these .tar archive things? I understand I need to compile using make & get & stuff, but theres no source code & compilers? I have all this crap on my slackware CDs but its in tar aswell. Help!

I specifically need to know what to do with the tar which contains my modem drivers.

Also, I understand DSL can eat .deb packages? How do I go about installing .deb's?

Thanks in advance.