Esportsdesk.com is your gateway to recreation sports on the 'Net: hosting the worldwide community of amateur athletes. (This is one of those "related" sites. They have their own postings at the very bottom, under Job Opps.)
JobsInSports, a monthly fee-based service listing jobs and internships.
NCAA News - The Market
Job opportunities in college athletics; click the Employment link near the top right of the screen.
SportManagementClub.com is an online resource dedicated to students interested in a career in Sports Business. (Click the dot next to "non-members" to start and learn more. There are two levels of fees to become members.)
Women Sports Jobs
With job listings "powered by Women'Sports Services" and other resources available.