Here is an intro of the importance of Maha Shivarathri, and what types of Poojas should be done - all explained by Sri Maha Periva himself.
Take a look at this link, and read it all for yourself (in Tamil).
http://www.kamakoti.org/tamil/shivaratri.pdf
Jaya Jaya Shankara!
Hara Hara Shankara!!
