snax,

Basic things to help secure WAP are:

Turn off your SSID broadcast - This will help, but only a little bit, it does not keep someone from getting your SSID only keeps your WAP from advertising it.

Turn on encryption - Turn on the highest level of encryption your WAP and NIC can negotiate. Wep is surely available, though not the best choice WPA is better. If you can, configure your WAP so that it is accessable only via VPN.

Turn on Mac filtering - Your Wap should alow you to specify those MAC addresses that are allowed to connect.

For more advise you should post the type, model, etc.. of your WAP and Nic that you are using so folks get an idea of what hardware to consider in their responses. If the folks here know what devices you ae dealing with they will be able to be more specific in their responses and you will be happier in the end.