Chips are easy. Just peel, cut into slices and either brush with oil and put in the oven for 30-40 minutes or shallow fry. The oven ones are really nice if you grate parmesan on them.
Another really nice thing to do with Celeriac is the following recipe... I can't remember which low carb site I found it on originally, but it's a great hit in my household and tastes absolutely sinful <g>
Celeriac Dauphinoise
1 celeriac
300ml double cream
100 grams mature cheddar cheese, grated
Dried mixed herbs, salt and pepper to taste.
Optional 2 cloves garlic
Cut the celeriac into quarters then peel. Slice the celeriac into 5 mm thick pieces. Place a layer in a baking dish and add some double cream and dried herbs, salt and pepper. Continue layering up. Place in a hot oven 200 centigrade and cook for 35 minutes. Remove from oven and add a layer of grated cheddar cheese. Place back in oven and cook until cheese is golden brown. Serves 4