I am running the same in VMWare and this is what I have done. Install SQLA on your host and configure your VM Guest to use Bridged networking. Then in your Host machine open SQLA and try to connect to hyperjcop1. It should work and should connect to your Guest TD express instance. You can then install Informatica and configure that connection as you would in any other Informatica instance.
That is all I needed to do, hope it helps you out. If it doesn't work as I described you could try adding an entry to your hosts file on the Host machine as Rob Paller mentions.
If that fails come back and post your errors or more detail about what you have tried.