How can I get the creator user name?

[muppetmad]

I would like to record the username of the creator as well as the time the record was created (seperate fields). I have a trigger to record the last editor but that runs for each change. Is there a way to create a trigger to only run when the record is created?

 

[muppetmad]

I see know that I can put getdate() and user_name() in the defaults of the fields to get the results I want.