2 hours 55 minutes actually Aslemma!!
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(but worth it eventually) There are several internet offices in all the major holiday resorts which are much cheaper than the ones in the hotels. Cost is normally 1 to 1.5 dinars an hour (as opposed to 10 dinars) and offices usually open at 11am. The taxi drivers will be able to point you in the right direction. Suggest that you avoid weekends when they are usually full of students.
There use to be a laundrette in Port el Kantaoui, but not sure of it is still there now. Go through the entrance to the marina - take a right turn and follow the small street along and the laundrette used to be there. As Alsemma said, all the hotels have a laundry service, but is normally quite expensive if you have lots of items e.g. T shirts 4 diners (£2) If you go in the summer months, any items washed out and put on the chairs on your balcony, will be dry the following morning - and the local shops sell little packets of excellent powder for hand washing. Hope that helps.