I would like my application to install Google Chrome along itself. I simply added a dependency named google-chrome-stable to the deb installer and it works.
However, it only works if the target machine has Chrome in its repository (which is not the case on a clean Ubuntu install for instance).
Is there a way to solve that? Can I somehow specify a URL or some other data that enables Linux to resolve the dependency?
To solve your problem with with google-chrome you can add a dependencie with chromium-browser which is in the repository.
I don't think it's possibile to automatically add another repository to met the dependencies of your package. You could add the requested dependencie in your package (if it fits) or fail the installation explaning to the user what repository to add and how to add it.
A good How to install it guide on your package web-site for example.