Some short notes on using GnuPG
To verify a file run
gpg --verify <sig-file> <data-file>
If you get complaints about missing keys, check the line that says
using DSA key ID <number> and see if you can import
the key from one of the key-servers with
gpg --keyserver wwwkeys.pgp.net --recv-keys 0x<number>
Otherwise check the site you got the data file from and if there's a
key file there get it and run
gpg --import <key-file-name>
List your keys with
gpg --list-keys
Sign a file with
gpg -b --armour <filename>
Encrypt a file (to ascii)
gpg -e --armour -r <Name-of-the-recipient's-key> <file>
Delete a key
gpg --delete-keys <Name-of-the-recipient's-key>