There are a multitude of really excellent resources online dedicated to teaching abroad. Some are obviously better than others, and they offer very different services. I can only speak from my own experience, but what I will say is that taking the time to research is a must.
Teach AnywhereI started with teachanywhere.com which is a free recruiting website. I was matched with a recruiter, and I was very impressed at the individual attention that I received. It was through this site that I interviewed for a school in Indonesia. It was a unique opportunity at a small school with lots of opportunity to really make a mark on the local education system. I was intrigued, but it wasn't the right time for me to make a move like that. I soon learned that any of the other job opportunities that came my way from this recruiting site were similar, small schools with development opportunities. It wasn't a good match for me because at this time I realized that I really wanted to pursue opportunities at IB World Schools.
ISSISS (International School Services), and I realized that I had to make that critical decision: if I was going all in or not. ISS is pretty expensive to join, but once you pay the annual fee, you have access to hundreds of jobs at some of the best schools in the world. It's not enough to just join and search the postings though. The head's of these schools want to meet you in person, and one of the only ways to do this is through a job fair. The drawback is that if there isn't one in your area, cost of travel can be pricey. For the 2015 recruiting season there will be fairs starting in December 2014 in Atlanta and others in Bangkok, Boston, and San Francisco at the beginning of the year. I opted for Boston because I was able to stay with my sister in her lovely North End apartment. It is always a bonus when you can work family into a job search.
Do Your Homework
TIE (The International Educator) and CIS (Council of International Schools) are also great places to look. TIE has a significantly cheaper membership fee too if you are short on cash.
The best thing you can do is keep an open mind, and don't focus all of your attention on one country or one continent. Some places are easier to get jobs than others, and some schools require very specific experience and training. Most of all though, don't give up. If this is something you truly want, the right job will come your way.
If you have any questions about how to teach internationally, leave a comment or send an email. I'm happy to help.