Unless he's got some sort of criminal record or problem with immigration why would you need a lawyer? They can't speed up the process, and in the majority of cases, all they're going to do is have you write up the paperwork by hand, then they'll type it and send it in. Why waste the extra time and money?
Check out the forums at
http://roadtocanada.com for info on marriage based immigration to Canada, lots of helpful people there. And the forms and everything are free to download at the CIC website
http://www.cic.gc.ca/english/immigrate/ ... spouse.asp