In case you are wondering what is going to happen at ICALP 2008, and when, I encourage you to look at the skeleton of the conference programme, which is available here. Some more detail is presently available for track B.
The conference organizers strongly recommend that you register for the ICALP conference and book accommodation before May 5th, as that date is the deadline for registering at the lower fee. After May 5th hotel rooms will also start to get released since July is the prime holiday season in Iceland and the demand for hotel accommodation is very high.
NOTE: For those who have not decided yet which workshop(s) they are going to attend when registering for the conference, it is possible to register for workshops at the lower fee until June 5th by sending an e-mail to the Conference Secretariat.