Ouch. That sounds quite hard. To the best of my knowledge, there isn't any way of combining another GUI kit with Allegro. Your best option would be to make your own text entry field. Draw out a box, and when the user clicks on it (check mouse position), a flashing bar comes up (you could leave that out). As the user types, it goes to a string which is drawn on screen (you would have a string of the input, which gets one letter appended to it at a time). That's just an example :)
You could use pygame. http://pygame.org/docs/ref/event.html Tips: Remember to "pump" the event queue on each update. Don't initalize a window, just use the console.
