Lyx package recommends sgml-tools, but...

[Paul E Condon <pecondon@quiknet.com>]

I just downloaded and installed Lyx using aptitude on a Sarge system. 
The package recommends also installing 'sgml-tools' which, from its 
name, sounds like a good idea, but the search function in aptitude 
cannot find a package of that name. Where might I find it?

Also, I am a beginner at TeX, LaTeX, etc. Please recommend tutorials, 
and 'getting started' documentation.

TIA

Paul

PS Reply to the list and CC me, or to me and CC the list. The list is so 
big now that I have missed things that are important to me.