A good layer will lay one egg per day for perhaps 18 months once mature. Most chickens will stop laying during the winter months however, you can put a light in the coop to stimulate laying. (we don't, but we used too)

A very good basic chicken book is Chickens in Your Backyard

To answer your question- we have 28 with 18 of them laying daily. In the next few weeks I expect to be overwhelmed with eggs.

The chickens have been a nice addation, there are hundreds of varities. Next year, we plan on doing some heritage turkeys.