To contact a student via e-mail, go to www.roch.edu. On that home page, you will see STUDENT/STAFF DIRECTORY. Click on it, and you will enter a search engine where you can easily find e-mail addresses.
NOTE: This will give you the student's RCTC college e-mail account (which is the official means of communication at RCTC). However keep in mind that many students have other personal or web-based e-mail accounts. Ideally the students have set up their RCTC e-mail to forward to their main accounts.