Most of it is already installed in your head - it's called common-sense. When using a punlic access WiFi hotspot:-
1. Make sure your firewall is running.
2. Access your email via a webmail interface, and make sure it has an https:// address.
3. Turn off file sharing in your operating system.
4. If you use hotspots a lot you should install a Virtual Private Network (VPN) application, like the one you'll see if you click here
5. Take a look around to see who else is nearby with a computer turned on.
6. As soon as you've finished, turn off your laptop's wireless adapter.
I use hotspots quite a lot, and so far I've been trouble-free.