We went to Alicante on the bus a couple of times at Easter, the GA centre bus doesnt leave the ga area, you need the buses
by Consum depending on operator some go down 332 others via Arenales ElAtet etc, they all arrived in Alicante firstly at the train station where we tend to get off as your at the top of town so nice walk into the centre then down to seafront area, the return is from the bus station by the marina, very well organised but can get busy at certain times. Unlike our local bus in the uk which averages 4 passengers per journey the spanish buses seem busy.