I'm presuming that you've already setup another machine that has IIS/Apache and a worker version of FMS on it, and the FMS service is currently running?
From experience, when you can't see the worker machine when deploying the web stuff, it's because some port(s) are not opened. You'll need more than port 80 to make this work. Check out the getting started guide, page 25
To see if it is a port, an easy method is to turn off any software firewalls on either server, and ensure there is no hardware firewall between them. I wouldn't suggest this in a production enviroment, but it'll eliminate the possibility of a firewall issue.
I have worker machine running on Windows 2008 R2 (IIS 7.5). I am able to ping the worker from Database (Master) server and also able to access port 80 via web browser (FM Default web page is shown happily). However, when i try to edit my Master machine deployment to "Multiple Machines", I always get an error message reaching the Worker.
I have also observed the Worker machine has only FMS13 Helper server running in the processes window (Task Manager).
However, for a FMS 12 working server setup there are some more exes (FM Web publishing, custom web publishing etc) in the memory. This successful setup has been running without any issues on Win 2008 R2 Data Centre edition. Do you think Windows 2008 R2 data Centre is a problem for FMS 13 alone? (I know FM 12 or 13 supports Win 2008 R2, but FileMaker Inc does not mention anything about its flavours - standard, enterprise or Data Centre etc).