You can freeze the lemons whole and grate the peel of the frozen fruit into anying which calls for lemon zest. As for juice just defrost one when the need arises,cut and aqueeze.easy!
I always end up with too many fresh lemons so I either wedge them or slice them thinly, freeze on a tray and then bag them and use them mainly win a g&t. You don't need ice cubes and it looks pretty too. Also do the same with limes and oranges, put a few in a jug of water if you have friends over, keeps it cool, tastes nice & looks pretty.