In Colombia, like in many other countries, there are websites that will help you find the job you want. There are also the traditional methods such as searching newspapers, speaking with other people, and visiting job posting boards.
For most of the ways to search for a job in Colombia, you need to be quite fluent in Spanish. The Colombian websites are in Spanish, and so are the classifieds in the newspaper. Here you can find a list of helpful websites for finding a job:
Depending on your industry, it often pays to network even before you arrive in Colombia. Professional social networks and expat forums provide the opportunity for you to connect with expats already in the country. They are often a good source of information when looking for a job, many of them were in the same situation once upon a time.
As in many Latin American countries, it is often who you know, not what you know. With this in mind, reach out to companies in your sector before you arrive, this will make it easier to find out about open positions.