Hi Gem, It's just under 2 hours from Tunis to Sousse. Medhotels have a cheap transfer that they do from Tunis airport to Sousse for only £5.05 each way. I've used it and can and do highly recommend it. If you want to book on line, go into
www.medhotels.com then transfers where you can choose which hotel you'd like to be dropped off at - Riadh Palms is one of them in Sousse. It's tremendous value for money.