The first step is to get your home wireless network configured properly. Bradley Mitchell, the About.com Guide to Computer Networking, has a fantastic and easy-to-follow primer on networking that's a great place to start.
Microsoft also offers a handy tutorial on wireless-networking basics that will help if you're using Windows. If you're using Vista and running into problems, troubleshooting guide will help. Next, learn more about the basics of wireless printing with a primer from Etan Horowitz of the Orlando Sentinel.
If you're trying to use a scanner that doesn't have a network card, you can find some useful software from Remote Scan.
