Watch how a dog house is constructed on Ron Hazelton's 'House Calls' site. It has a great video on how to build a basic dog house. It will help you build your own dog house with step by step instructions. And it's free.
Check out some simple designs. Lowe's offers a plan for building a dog house for beginner and intermediate skilled builders. It is a design that should be able to be completed within a weekend and one that can be a family project.
Look at more involved designs before deciding on what you want. Another more complex dog house building plan is offered by Things-to-Build. This one is a solid, all wood construction with measurements in both feet and meters.
Explore designs being done in other countries. Sally & Hal from Australia offer and interesting A frame dog house that should be very easy to build. The only problem you will run into is that the dimensions are all given in meters. But the design should be easy enough to follow even if your math skills aren't up to scratch.
Look for an insulated design if you live in a cold-winter area. You can find a plan for an insulated dog house from Wayne of the Woods that is both easy to build and will make temperature changes more comfortable for your four-legged friend.
Of course, you can also buy a ready-made dog house or kit. These are not free, but most are easy assembly and are not expensive. The 'Precision Outback Country Lodge Dog House' (pictured) costs about $100. The standard vinyl igloo designs can run from an estimated $10 to $90. Igloos can be found at most home stores and pet shops.
Along with the links for all the dog house plans mentioned above, you can also find more information and a list of sites for prefabricated dog houses listed under the Additional Resources, below.