Does the "Writer's Market" book contain email-addresses for the publishers and agents listed?
I’m trying to sell my novel, and I much prefer sending email queries because I hate wasting ink/paper. I want to know if buying Writer’s Market is worth it to me- does it just list the agents’ addresses, or does it also list their email addresses?
Actually, judging from the websites of the agents’ websites I’ve already found, a lot of them are starting to prefer email.

Yes.
However, the VAST MAJORITY of publishers and agents DO NOT accept email queries. Fair or not, it is considered unprofessional and marks you as an amateur.
It will be deleted in the blink of an eye.
If you’re serious about publishing, do it right. Take the time to print out a hard copy of your query and/or manuscript, package it neatly, and send it out.
~Dr. B.~