It sort of depends on what type of tourism business you are promoting.
I would start by looking at your type of business and your current content offering. If you are a hotel, what level of content do you provide about your hotel, your services, the destination in which you are situated in and the attractions nearby.
Can you deliver content via an eNewsletter program that creates more awareness of your product/destination and can you tie that into targeted offers to potential customers.
Running a competition will quickly build a database, but unless you have good content to send to the database then they will quickly tune out.
Search marketing is critical for tourism businesses as much of the planning and an increasing level of booking of tourism products is happening online.
Consumers are also trusting 'marketing content' less and are looking for content from other consumers hence the rise in popularity of sites like tripadvisor.com.
Tourism/travel is very much about the location so maps are very important. People want to know where they are staying or visiting in relation to landmarks, attractions, beaches, conference venues etc, Map related search terms around destinations have extremely high search volumes further highlighting their importance.