All Staples stores have a shredding box where you can bring your files. You could also bring them to your office shredding box. The most important info to destroy would obviously be your name, address, SIN number, etc. That info is always listed together so you could cut it out with scissors and take a one hole punch to shred it smaller. Financials are not much use without the name, address, etc.
The other thing to do is sign up for online billing wherever possible so you don't have to worry about piles of paper to destroy.