You can just use the eventlog, by creating it on the fly and then using it.
The eventlog which should be created as an Application Eventlog on a NT
based O/S can be viewed with the Event viewer on another machine across the
LAN. I have done this with Console and NT Service application, and I don't
see why you couldn't do it with a WCF solution.
The example is in VB.Net but you can do the same thing in C#.Net