Umm I guess you can open Task Manager (Ctrl+Alt+Del) and start the process explorer.exe ? I'm sure it will work since this already happened to me and I do this everytime it happens.
EDIT: Welp didn't read the last setence <.<. What do you mean by wifi adapter? The physical thing you mean?
This'll help with the wifi adapter: http://internethelp.centurylink.com/internethelp/os-windows-8-ipv4-enable-network-adapter.html (http://internethelp.centurylink.com/internethelp/os-windows-8-ipv4-enable-network-adapter.html) In this link they do use the charms bar, but as long as you can find the control panel you'll be fine.
Ok, now the charms bar is gone? That's strange... Maybe this will help there: http://answers.microsoft.com/en-us/windows/forum/windows_8-performance/missing-in-windows-8-charm-computercontrpanelhelp/9969eb18-757c-49d2-a2a0-df677c2c4c20 (http://answers.microsoft.com/en-us/windows/forum/windows_8-performance/missing-in-windows-8-charm-computercontrpanelhelp/9969eb18-757c-49d2-a2a0-df677c2c4c20)
http://answers.microsoft.com/en-us/windows/forum/windows_8-performance/charm-bar-windows-8/f2e89176-921d-43a6-bd35-e5b179b51592 (http://answers.microsoft.com/en-us/windows/forum/windows_8-performance/charm-bar-windows-8/f2e89176-921d-43a6-bd35-e5b179b51592)
Also, have you made any changes before it happened?