Is there a way to block my mac address from showing online?

yeah, go into your wireless network mgr, also a good way to help out your security level EDITED i may be wrong but isnt ur mac address the wireless nic cards I D i think im right but u check it out and let me know?!? go to network mgr log in & click on MAC ADRESS CONTROL & i dont know if the default is hidden or not but added level of security is to hide it good luck!!