You can get such Q&A easily from online, like Monster, Wetfeet... or simply google it. Also I am sure the career centre of your school has such information as well.

It is a courtesy to send a Thank-you letter after your interview. You can send it later that day or more likely, the second day. Email is fine, nobody uses mail right now :) Try to get all the interviewees' email address and send to them all. You can find such template online as well.