I'm sorry if this has been asked, but I don't see it in the FAQ and a search of "play by email" turns up no hits. 
My LAN is temporarily down, and I'd like to start a game now, rather than waiting until I resolve the LAN problem.  
Can some kind soul please point me to instructions for hosting over email?  In particular, what files do I need people to send me, and what do I send them back.  Anything to watch out for in terms of switching back to LAN after playing by email?
Thanks,
Merry     
