If interested in booking travel for another user, Melon gives you the opportunity to do this easily via the Trip Arranger feature.
To book travel as a Trip Arranger:
Login to your Melon Account.
Type the name of the user you want to book on behalf of in the Traveler box. Select the name of the user applicable, and continue on with the booking as normal to confirm their travel on their behalf.
Note: Not seeing the name you need? Click Here to ensure they are listed as someone who you can book travel for in Melon.