You can do it your self by going into your routers configuration. Since I see your new to this I would recommend using the setup disc that your router came with, this will set everything up for you such as naming your router and setting secured wireless connection.
Basically for wireleaa security , changing the ssid, channel, hiding the broadcast of the above are a waste of time since there are programs like net stumbler that will discover these. Mac tables can become alot of work if you have a lot of computers. The only one that will keep ppl from surfing in on your wireless is encryption. WEP is good, WPA is better, WPA you have a certain amount of time to enter the key in your workstations, before the key expires, this is good because even if someone discovers the key, they can not enter it after the time expires. WEP the key can be entered at any time. Also change your log on password to the router, tape it to the bottom of the router, unless you are in an office.