Many organizations and associations gather statistics in their area of interest and publish them on their websites and in their publications.
At the American Cancer Society you can find out how many cases of prostate cancer were diagnosed last year and the National Restaurant Association can tell you in what city people spend the most money eating out.
Below are websites that list associations. If you can't find one you need, try googling your topic and the word association.
Asking these questions will help you to determine whether the resources you find are credible and reliable.
Who created the page? Does the person or organization have the appropriate credentials?
Why was this site created? What is the purpose of the site? For example, is it sponsored by a company that has a financial interest in the topic?
When was the page created and/or last updated? How current is the information?
Does the author cite trustworthy sources? How does the author support their argument?