The time to act is now.
There is a really excellent template letter to send to the PM, and your MP if you are not in support of the proposed DMCA bill coming before the house in six weeks.
If you disagree with Canada introducing, in six weeks, DMCA-style copyright legislation for Canada (i.e. anti-consumer, lose-your-internet-service-for-sharing-a-file copyright legislation), feel free to copy, customize, and snail-mail the letter below.
For your letter to actually get read, you need to include your complete mailing address.
(You can email it too, but you don’t need postage to mail the House of Commons and paper carries more clout.)
More more information on Canadian copyright reform, visit Fair Copyright for Canada, which has excellent resources listed.