We use Ethernet because it requires no configuration or passwords, just click the cable to get DHCP but if you want, its possible to set it up as a WiFi-to-WiFi proxy. You'll need two WiFi adapter, then edit /etc/networks/interfaces to add wlan1 and enter in the SSID/password for your Internet provider using our WiFi tutorial We don't have a tutorial for this project
Its very easy to configure tor to give you a presence in any country
of your choice. For example here's my torrc that makes me 'present' in
Replace aaa.bbb.ccc.ddd by the IP address of your RPi and GB by the country code of your choice.
Configure your browser to uses a Socks 5 proxy on aaa.bbb.ccc.ddd, port 9050
Log notice file /var/log/tor/notices.log