If you haven't been able to buy Alhambra tickets all may not be lost.
You can go and get in a queue early in the morning because they hold 2000 tickets back for sale on the day.
But what is the earliest you can start queueing?
I just phoned the Alhambra and they say that the Alhambra opens to the public at 8.30 but it is best to get into the queue at 8am.
I suppose on days of very high demand like Easter it may be a good idea to get there a little earlier.
Also don't forget that it is sometimes possible to buy tickets directly from the yellow machines with a card.
I would recommend that you have one person in the queue and one person trying to buy a ticket at the machines.
You can see pictures of the yellow machines here.http://granadainfo.com/alhambra/day.htm