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I started to play with only controller supported games since i've bought one and there doesn't seem to be a controller support logo in games' pages.
This question / problem has been solved by djdarkoimage
Generally games will say if they support controllers, for example Guacamelee:

Says this in the details:
Controller support: Supports the Xbox 360 Controller and other XInput-compatible controllers.

When in doubt, check the game's forum page, and ask if the question isn't already presented.

I believe you can also use a wrapper that maps keyboard keys to your controller keys, you should be able to find something like that through Google. examples, JoyToKey, Xpadder...
Post edited May 01, 2014 by djdarko