In the city of Alkmaar and the nearby seaside towns are various hotels, guesthouses, bed and breakfast places and hostels to be found. See the following websites:
Alkmaar Tourist Office
During the festival there are lots of other things to do and see in and around Alkmaar. There is of course the weekly cheesemarket everyday Friday morning, where you can see cheese being traded in the old, traditional way.
At a stone’s throw from the church you can find a museum and a theater and the city also boasts a filmhouse: Provadja.
Lots of places to eat are scattered all over the city, catering for all tastes and all price-ranges.
And if the weather is nice: beaches and the sea are very close by !
More detailed information about what to do in Alkmaar and the region you will find on the website of the Alkmaar Tourist Office