There are many ways you can contact staff. The easiest would be to contact them on IRC. If the staff member you're trying to contact isn't available, try sending them a memo. If you are not sure how to send a memo, check the Q&A, or ask someone. Please try to work it out yourself using the Q&A first. If you find you can't, then ask for help in the #help channel. After you send the memo, please be patient and wait for a reply.
If you are contacting the staff to appeal a ban, you can also email appeals [at] caelestia [dot] net, including the nickname you were using at the time of the ban and why you believe the ban was unjustified. Please be prepared to wait for a response as the staff confer over the matter.