missing wireless adapter-it says

I have been using Netgear USB router on my Dell notebook Latitude 600 running Microsoft xp for 6 months now but lately, my little wireless balloon icon on the bottom right of my desktop screen has a red X in it and now I cannot log onto the internet; even though my router is working fine and I can see I am conneceted locally on wireless. I have tried most everything imaginable. I have rebooted, did system restore, checked this and that and read until my eyes hurt for nearly a week now. I am in Ukraine and they have wireless places here but now it does me no good. What is wrong and how do I fix it? Thanks