I recommend buying a Perl book or two. Although "Perl Programming" (the "camel" book) is the canonical reference, it seems, you might be better served by "Learning Perl" (the llama book).

"Learning Perl" does have chapters on CGI, among other things.

After that, start looking at the modules that have already been written for things like generating HTML. Modules are just someone having already done the dirty work for you. :)