Poor you, I you go out after dark you will see them (especially if its been wet) and can collect them. There are traps you can buy or make your own beer traps. Or you can get slug pellets but some can go through the food chain in your garden wildlife such as slug-frog-cat. Very sharp grit or eggshells around individual susceptible plants can help protect them.

Put a pond in. This addition to my garden brought many more frogs into the garden which caused the slug population havoc. This year has been bad so I have resorted to pellets. Drc726 is right about some slug pellets causing a problem but there are those that are safe so read the labels. To be safe put them under a tile or piece of wood to draw them in and keep their dying throws out of sight from predators. Putting old carpet down gives them a place to sleep so they are still their in the morning for you to despatch. Are you a hands on slug killer or do you prefer the 'do it quietly at a distance' approach?

Slug pellets do most harm as birds will pick up the dead and dying slugs and eat them, thus poisoning the birds. That is why you should always use pellets under a container and pick up the dead and dying slugs and snails immediately the next morning.
A better way is to put down lots of upturned containers, or black plastic sheet or even thin boards. Slugs and snails like nothing better than hiding under places like this in the day time, so no torches necessary, just turn over your 'traps', put them in a bucket and carry them all off to the garden of your most unpleasant neighbour! (as long as they live half a mile or more away!)
Slugs and snails ARE like homing pigeons and will come back unless you move them a really long distance.
Alternatively, you can sentence them to death in salted water! (the slugs, not your unpleasant neighbours!)

Hens love slugs and snails so if you have space for a few you could give them the bucketfuls you will collect.

Again thank you all for you suggestions , I will try each one in turn starting with the beer traps. befor Slug pellets ,

I am a squisher, go out in my boots a few times a night after watering or rain with my disposable gloves on and squish the blighters, I also turn over rocks and move pots to find thier hidey holes.... After a month I'm finding less every night. I really want to avoid pellets as my four year old loves helping and getting her hands in the soil x good luck battling the slime brigade x

Snails tend to hibernate in groups attached to a hard surface so its worth while hunting around in the autumn. You can detach them, put them in a plastic carrier bag and bin them while they are all fast asleep. Or if you have thrushes you can leave them out on display for them.
Won't help this year but it does help to cut down on the ones you missed. When you are doing your spring or autumn digging look out for small collections of bright white eggs, and put those out for the birds too.