I'm looking for a game pad typing solution for dual joystick typing.
Stipe, is an open source (linux) software that is set up to use two joysticks to type.
http://www.thumbs-up.fi/products.html
Switchblade pro is another, however I believe it is going commercial.
http://www.switchbladegaming.com/whatis.cfm
The orbitouch keyless keyboard was originally designed to remove repetetive finger and wrist movement, switchblade was a software adaptation for use with xbox controlers that had dual analog sticks.
I've been looking at the older versions of Xpadder as one possible solution for this.
If you are wanting to remap keyboard and mouse input to a gamepad you can use AutoHotkey or Autoit. With a little time and patience you can make a portable application to do exactly what you need. And there are examples online, some of which you may be able to adapt to your purpose.
If you want to type using a gamepad or joy stick... I am not sure what your options are. To be honest, up till now I have never heard of such a thing. Sorry.
EDIT:
You already mention Xpadder, this appears similar:
http://www.electracode.com/4/joy2key/JoyToKey%20English%20Version.htm
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