Start by changing ALL passwords, immediately. Email should be the first since people can request passwords and have them sent to your email address. If they have your email, they probably have access to other accounts.
Then store them in an encrypted format. Have one master password that you remember, store the rest in a password keeper such as KeePass which is freeware.
KeePass is a free open source password manager. Passwords can be stored in an encrypted database, which can be unlocked with one master key.
keepass.info