Hello
I just filed tax returns for my wife and myself for the first time in Canada.
I bought QuickTax for 39.95 and did both returns, federal and Quebec, for both of us. It's pretty decent software and walks you through the process by asking a series of questions about your situation.
Also, check out this link
http://www.cra-arc.gc.ca/tx/ndvdls/vlntr/nd-eng.html. Revenue Canada has tax clinics all over Canada who can help you file and get all the credits you are entitled to.
I would suggest going to one of these clinics as filing returns can be a daunting task if you are doing it for the first time. Even with the software, both returns took me about 7 hours to prepare.
Good luck.
P.d.R