Apart from the IC methods listed in help roleplaying there are several forms of communication in game.
Notes is one such method and allows leaving of messages, either ICly or OOCly to one or more people, see help note.
There are also the newbie channel. Newbie is used for helping new characters. Used by newbie (message) or (channel) social (social) or (channel) emote (emote)
Aid can be used to send an ooc message to new players to help them out.
The STalk channel can be used by SRs to talk amongst themselves, and also by players to contact the SRs.
Typing the channel name by itself will also turn the channels on or off.
Immortals may send players private tells, and Story Runners may send them private STells. In both cases reply can be used to respond.
Players may contact the staff by creating a petition, see petition for more information.