I have heard Token Ring\Ethernet broken down like this:
Token Ring is like traveling by train, the packet of data waits at the station until the train comes at which time it gets on and goes where it needs to, if you miss the train you wait until the next one comes by.
Ethernet is like traveling on the highway you wait at the entrance until there is a free spot that you will fit into and you get on and go with the flow which is constantly moving in an endless stream of data.
As for training in fiber you can take a look at LightBrigade.com they have a course called Fiber Optics 1-2-3 that I am interested in taking possibly in March 06 when it comes to my area. Also just about every manufacturer has courses to certify you for their product. I know leviton has a course geared towards their residential product line. http://www.bluevolt.com/training/lin/CourseDetailsWiring.aspx