If so, what are some great places you would recommend i should goto? I like clubs, clothes, beaches, dining out and sightseeing/photography.

I found a brilliant little island when i was out there, called Ko Kradan, if you have seen the film 'The Beach', it is pretty much like that. At least when i went, about ten years ago, it was completely unknown to the general tourist. Although it could have been wiped out by the Tsunami. You'd need to get to a town called Trang far down the Southern peninsula to get a boat there.

Pattaya. Walking Street. Period.

I'm going to Thailand in a couple of months so I can't say for sure what are must sees. I am a pretty good planner though and think these are worth checking out.

1. Bangkok obviously
2. Chiang Mai
3. If you love hiking then Khao Sok National Park
4. In terms of islands... Phi Phi Island/Phuket is where you need to go to actually see "The Beach". Also check out when the full moon party is happening. If you love to party definitely go during that party, people fly out from everywhere just to see that party supposedly.
5. If you want a deserted island Ko Lipe seems to be a good destination.
6. Also check out the ancient capital
7. If you have time try going to Siem Reap in Cambodia.

These are a few off the top of my head. Lonely Planet seems to be a good resource.

That's quite a list. Be sure to post updates after you get back.

I agree with emeraldBee. These are my favorites too.