Encrypted email is very good - just make sure it is a reputable encrypted email provider (ie hushmail , which is what elitefitness uses). As far as a computer on a public library, their are better ways.
If you are truly paranoid, and everyone should be, you can use a bootable CD with a complete OS. Use this to connect to a Relakks (
https://www.relakks.com/ ) account (VPN through Switzerland).
After a reboot, their is no trace on your home computer. All transmissions go through an extremely secure encrypted tunnel to switzerland where privacy laws make it virtually impossible for any goverment to get your information... For that matter, since it is prepaid, you don't have to verify any information.
If you use a public terminal, you are still at risk. Sadly, libraries sometimes use proxies and logging. Further, it is easy for L.E. to "intercept" traffic from a public terminal, without a warrant.
If you truly want a completely secure untraceable browsing and email session, do the following.
1) Download and burn Knoppix, or another CD or DVD based linux ditro.
2) Create a Relakks account (5 Euros a month)
3) Connect to Relakks through VPN.
4) Connect through Relakks.
5) Create a hushmail account WHILE CONNECTED THROUGH RELAKKS. This is important. By doing this through Relakks, and only accessing it through Relakks, the IP logs will always lead to nothing. NEVER ACCESS IT ANY OTHER WAY.
6) Reboot. Now their is no record, and no way to trace your internet access.