For general industry overviews, market research reports, and articles search terms like: TRAVEL, TOURISM, TRAVEL AND TOURISM combined with terms like INDUSTRY, MARKET, FORECAST or TRENDS.
Also, look at resources pertaining to the Hospitality industry (hotels/lodging and restaurants) on our Hospitality research guide.
There are a number of niche tourism associations catering to specific clientele, industries or sub-markets. Some examples are 'golf tourism', 'LGBT tourism', 'culinary tourism', and 'religious tourism'. Search the internet to find associations affiliated with these types of tourism. Listed below are more general travel and tourism association resources.