Whenever you have questions or problems about your accounts or the department's computer systems, send Email to staff@cs.umd.edu. For serious problems (like not being able to send Email), you can visit the student staff office, AVW 4120, or any of the full-time staff offices, 4117, 4119, 4183, 3439, or 3441. You can also call 301-405-2720 to reach the student staff office.
Remember to always leave staff@cs.umd.edu in the To: or Cc: headers on all E-mail correspondence related to your computer problems. We're a team, and all need to be kept informed of what's going on, what's broken, and what's been fixed. If you only contact individual people, response times will be slower because different parts of the team aren't aware of your situation.