The first place to check is under the "Evaluation" link in your course site. If you do not have access to the course eval results, keep in mind that it can take some time for them to open after grades are submitted.
Additionally, departments can place restrictions on what faculty members can see and when. Please check with your departmental administrator to see if/when results are released.
Finally, the CourseWorks team, which administers and supports the evaluation system, can help. Feel free to email them at courseworks@columbia.edu or call 212-854-1919 for further assistance.