Hostels: how far in advance?

How far in advance should I be booking Hostals for mid June? I am studying abroad, and just now found out the date that my finals will end. I am going to Madrid for a week following the end of the program, and worried I am not going to be able to find any good hostals this late. Help!

Look around on the board, kelar419--many of the hostals that have been discussed here have e-mail contact information. I would suggest doing it now if you want the widest range of choices.

Have fun!