Do you mean naturally low in alcohol or wines that have been processed in some way to take some of the alcohol out, poshpaws?
Although it has had a bad press in recent years, a lot of German white wine is lower in alcohol than French/Spanish/New World.
Oddbins and Bottoms Up can recommend you some good, estate wines in that price category from the Rhine and Mosel regions
There is a lovely, but not easy to find, French sparkler called Clairette de Die, which is naturally low in alcohol, and delicious.
I think Italian Prosecco is also lower in alcohol than champagne.
Can't help with de-alcoholised products I'm afraid and I guess the one problem with wines that are naturally less intoxicating is that they are sweeter, with higher sugar levels...
They do say that good champagne is the lowest calorie wine