Hello disturb:

If you are new to web building,
Get the basics right ... Try to study html, java, stylesheets ...
Though you get many programmes which aid u to create webpages, though u are an utter webdesigning newbie.. But it is allways better to learn the abovementioned stuff.
Most webdesigners do not start altogather from the scratch. They desing the basic layout of the webpage by using tools like.. Frontpage Express, Coffeecup Stye Sheet Maker... Then they edit the source wherever required.

Now about the security measures.
*Host your sites only on reliable protected servers.
*Have a backup of your website with you.
*Encrypt passwords, and store them in separate servers isolated from the internet.
*Other designing techiniques.. depending on the programmer.. U'll learn when u them when you learn designing.

Its almost impossible to discuss all security measures... If we could, there wouldn't be web defacements at all

Hope that helps.
-XN