Tunisia has been making wine since roman times. My favourite is red Vieux Magon, athough it also comes in white. there is also I believe a sweet desert wine called Muscat De Tunisie. Local alcoholic drink is Boukha (a spirit) and Thibarine (liqeur), both made from figs. For my taste they are too sweet. The local beer is Celtia, a lager style beer available in both alcoholic and non-alcoholic versions. Opinions differ on this. I've known many Brits see it as an acceptable lager but Willieg would disagree.
When eating out be aware that some, though not many, restaurants do not serve alcohol as their owners are good muslims. Check before ordering. Brand names spirits are more expensive than locally produced versions. Again they are not to everyone's taste. If you are a fan of Gordons then fetch some dutyfree with you.
I think you will find Tunisia has changed lots since you were last there. On my first visit it was impossible to get anything other than shay (arabic style tea) or qahwa(coffee) in cafes. Now they all have cappucino machines and some don't even want to serve qahwa as it takes longer to prepare. Even in the hotels you dont get shay or qahwa on a regular basis. and you will find women workings in shops, cafes and hotels. that certainly wasn't the case way back when my Tunisian adventure first began. In restaurants beer and wine used to be served in mugs so as not offend others and not to attract the attention of the police. Oh, and you will struggle to find an arabic toilet too (now that's a change for the better) unless you really go upcountry.
However much remains the same; sunshine, haggling in the medinas, the friendly, funny Tunisian people.... Have a great time Inchallah.