LC 120, 4:30 to 5:30, Thursday, and by appointment. I'm occasionally a few minutes late so if you show up at the stroke of 4:30 and I'm not there, please hang out for a few minutes. My phone extension is 4093. You're unlikely to reach me there except during office hours.
Address email to me at elharo@metalab.unc.edu. Since I get far more email than I'm able to respond to, please identify yourself as a student in my class and include "CS905" in the subject line so I'll be sure to answer you.