I'm thinking of opening a bar or small shop in Poland selling beers and spirits can anybody tell me what the licencing laws are here,I have a licence to sell alcohol back in the UK would that licence be valid here,
The licence from the UK is not valid in Poland. You should apply for a licence here. You have to fulfill the specified conditions to obtain a licence. But I think it'll be no problem.
Firstly you have to register you business activity in Poland by the Office (or Court - it depends on it which legal form would you like to choice), apply for Tax number and Statistic number.