- Change the default SSID and Administrator Password
- Enable MAC address filtration to only allow PCs you know to connect
- Limit DHCP to the number of addresses you need so that you will have IP conflicts if someone gains unathorized access
- Disable SSID broadcast if your router supports it
- Install a personal firewall on each of your computers - this will not only help if your home network is compromised, but also protect you when you use public hotspots.
In any case, netgear has a similar document on their web site. Needless to say, it contains a lot of advice specifically about their products, but it is great generic Wi-Fi security info.