We had a very fun experience at the Ironbar grill on Macrossan. They have Cane Toad races in the evening. We participated in the race and had a super fun and unique experience. Food was pretty good, too.
Nearby supermarket - Coles can satisfy any needs on food. Lots of good restaurants along the street. A 1 day tour to Low Isles for snockering, operated by Saleaway, is fabulous.
Tours to Great Barrier Reef leave from within walking distance (10-15 minutes). Tours to the rainforest, river cruises, Kuranda (skyrail and scenic railway), pickup at hotel.
We only had four days there. Spent time on the beach, shopping, one day into the rain forest and one day snorkelling on the Great Barrier Reef. The last is not to be missed. Even if you have never done this before -- a must do. The highlight of my entire three weeks in Australia.
Port Douglas is a comparatively small community spread over a large area along the 4-miles beach. You will find a large number of good restaurants for every budget. You find very well assorted supermarkets for your daily shopping requirements - and if you want to spend your money on vanity, the Marina is the place to do it, as well as the weekend market.