Possibly the best around and avoiding the now normal contesting clutter is iCW.

Chuck - AA0HW has pioneered this for many years. He and I are sorta coat tail members of the St. Louis QRP Society. 

Here are several URLs to view. iCW reflector is,

A new group is now up on groups.io, 

Internet CW webpage is a good starting foundation,

QRQcw is a live gathering of how to accomplish a good station,

You will need a high speed Internet connection which allows you near full duplex.

There are more QRQ websites so please use your search engine for Internet QRQ.

73,