Not all roles or candidates are eligible for the company to provide a work permit. If this is the case for you, then there may be some other options to allow you to enter Canada on a work permit:
International Experience Canada (IEC) provides young individuals (18-30) the opportunity to travel and work in Canada. IEC is available in countries that have a bilateral youth mobility arrangement with Canada. For more information, please visit: http://www.cic.gc.ca/english/work/iec/index.asp.
The SWAP program allows individuals from the United States to obtain a 12 month open work permit for Canada. You can find out if you are eligible here: www.swap.ca.
The Post Graduate Work Permit allows graduates from a designated learning institution to apply for a post graduate work permit. You can find more information here: http://www.cic.gc.ca/english/study/work-postgrad.asp.