We all can probably think of several reasons why computers might not be the most environmentally responsible products around. The many parts of any one computer will have been made in as many different factories around the world, then shipped somewhere else where they are assembled with certain other parts, then shipped somewhere else for further assembly and fine-tuning until eventually, they end up on your desk. They contain many ingredients in their respective parts that must be considered toxic, and they are renowned for their lack of durability. Yet most of us here in Canada must use them every day-often at work and at home.
Greenpeace puts out a Guide to Greener Electronics to help you evaluate which huge multinationals have a policy on environmental responsibility available on their web sites, and who is actively working at reducing toxic and non-recyclable components, increasing in-built capacity for up-grades and expansion to increase the life of the machine, and energy efficiency. They are also looking at shipping and fleet emissions issues.
Another resource may be ReBOOT Peterborough, a non-profit organization that takes many used computers and refurbishes/recycles them for use by low income and non-profit users who may not otherwise have access to this technology. You may be able to buy a computer from them, or they may be able to help you recycle an older model you have at home. They are listed under links.
Do assess your needs when buying a computer. A second-hand version may well be all you need for simple word processing, spreadsheets and other programs. Several local computer companies can help you set up a used system to suit your needs. They are listed in the "Where to Buy" section here. Dell sells computers online, so their site is listed in the "Links" section, along with ReBOOT Peterborough. If Hewlett Packard works better for you, then look for environmental certification of individual systems. They are commonly available at business supply stores and their web site is in the links section below.