We don't know what the ipage template structure looks like. If it follows Zen Cart standards, it will probably have an /includes/ folder that holds all the rest of the files and folders; if so, that will go into the root of your ZC installation alongside the existing /includes/ folder (the two will merge into one).
There should be instructions from the template provider for installing. If there are no instructions now, what do you think their support will be like later?