I leave for Bangkok in 3 days. Any advice on where to go, what to see?

I�m backpacking so any advice on extremely clean but cheap hostels would be good. I�m a photographer so need to know where�s beautiful. Where�s good to eat? (and again che4ap because I�m almost broke!) and any general advice would be hugely appreciated because I�m pretty nervous. I�ve traveled a lot, but not in Asia and worried about the culture shock. Thanks