You can manage Two Step Verification for multiple Google Authenticator Accounts with just one App using Authy, it is very simple:
You can also add tokens from Websites that support Google Authenticator such as GMail, Dropbox, Lastpass and Amazon. Each of these websites have a different way to enable Two-Factor Authentication, but you can usually find the enable page on your user settings page. If you are unsure, contact their support staff. Once you enable two-factor on the website, they will present you with a QRCode image. Use the Authy App to scan that QRCode and you are set.