I'm no LIRC expert, but I thought the idea was that it could take any remote signal and perform any action. So just pick any device on any existing remote and associate the signals of your choice with the actions of your choice. You don't have to generate or capture any codes. You use existing ones and define them to mean whatever you like. Doesn't matter what they are.

As for the smartphone solution. It works perfectly fine with an old, cheap iPod touch on your local LAN with no phone service whatsoever.

I've tried to do it all on a single remote, and while it works ok, it's much easier to pull out a second device for PC control that actually works well. I don't use the phone for my IR remote.

The device you linked reminds me of Jemaine's camera phone on Flight of the Concords (he duct taped a camera to a phone). I've used similar devices, and can tell you that they suck. The range is typically abysmal and the remote can't do macros or very many devices. And the keyboard part of that remote is RF, not IR, so it's impossible to learn. If you manage to find an IR keyboard, it will speak IRDA, not consumer IR and will also be unlearnable.

Sorry, but I've been down this road before.