There are several graphical (and one command-line) interfaces for FANN.
FANNTool is a highly recommended and easy to use GUI for the FANN library. FANNTool also supports a few more advanced functions for automatically setting the FANN parameters.
Agiel Neural Network
Agiel Neural Network is an easy to use interface, that is centered around the training data and provides options for visualizing the difference between the neural network output and the actual output.
NeuralView is a neural network simulator, with a multi-platform graphical interface.
sfann s a command-line tool that provides an easy way of learning, testing and running artificial neural networks (ANN). It uses the Fast Artificial Neural Network library (FANN) for learning and testing.
If you know other user interfaces for FANN please let me know, by sending and email to firstname.lastname@example.org