If there is one place you must go to catch a sunset on the island of Phuket, it's Promthep Cape. Located on the southern tip of the island near Rawai, Promthep Cape is a very popular attraction to locals and tourists alike, so its best to arrive somewhat early during high season if you want to snag a good spot to take in the breath taking view of the sunset. I have been about 7 times during my 3 years in Phuket, and only once has the sunset been obscured by clouds, so chances are you'll be able to see what all the fuss is about.
For the first 6 months of my stay in Phuket three years ago, trips to see cultural landmarks like the Big Buddha were few and far between. It wasn't until my friend Matt from Boston, Massachusetts came to visit for a week that I ventured farther than the beach. And I am glad I did.
Still under construction, the Big Buddha monument is a massive undertaking being built on a mountainside in between Chalong and Kata. You must drive up a steep, somewhat dangerous road to reach the base of the statue. This is one destination where I recommend taking a tuk-tuk or better yet a metered taxi if you are not completely comfortable with driving a motorbike under less than idela conditions. But once you are there, you won't regret having spent money on a ride. The view from atop the hill overlooking Chalong Bay is remarkable, and Big Buddha up close and personal is definitely cameras worthy.