Personally, I use Nvu as my favourite HTML-editor. It's free, it works on multiple platforms and its HTML-code is relatively straightforward and clean and therefore easy to "cut-and-paste" into your scripts or templates.

For an entry into CGI, there is of course no way around Ovid's CGI-course.

If you have any specific questions, you will find Perlmonks a good place to ask them. Please, ask only specific questions, add some code you have written, show the Monastery you made a genuine effort of finding a solution and you will find the Monks most helpful.