I have some download link on web site that has a google analytics on click event
I also have an AdWords and Facebook campaing running
I would like to know if click on Events are from AdWords, Facebook or organic search
Is it possible?
Yes, the source is the source. Check whether your adwords is linked to your GA account, and being tagged, if you're not using utm tags, allow automatic tagging.
Yes, when you're looking at your events report, just add source / medium as a secondary dimension.
You can also get more exact information on the source / medium by using utm tags, then you can name the campaign, and look for that rather than the source. That way you can distinguish bewteen, for example, any variations in ad content.