Nicky,
You didn't list the recipe that you are using. I'm wondering what type fat you are using in the recipe...butter or margarine? If using margarine, you need to use one that has at least 100 calories per Tablespoon and 11 grams of fat otherwise they will have too much water in them and cause the cookies to spread. I just use margarine and find that Land O' Lakes Margarine is the closest thing to baking with real butter.
I find if the batter is not as solid as I'd like, I add some oatmeal (whatever you have on hand old fashioned or quick oats) to the recipe. You can add 3/4- 1 cup without really affecting the taste of the cookie and this definitely seems to thicken the cookies up.

Chocolate Chip cookies
3 3/8 cups flour
1 1/2 tsp. baking soda
1 1/2 tsp. salt
3 sticks margarine (Land O' Lakes)
1 1/8 cup brown sugar
1 1/8 cup sugar
3 eggs
1 1/2 tsp. vanilla
1 3/4 cup chocolate chips
3/4 to 1 cup oatmeal
Pre-heat oven to 375°
Cream margarine and sugars together. Add vanilla mix well. Add eggs, mix well. Combine dry ingredients together. Make sure that baking soda is fresh! Gradually add to sugar mixture and mix well. Fold in chocolate chips add nuts (if desired). Roll into balls and place on an
ungreased cookie sheet. Bake 8-10 minutes. Let stand on cookie sheet for a few minutes and then transfer to a wire cooling rack.

Nicky, Please let me know if any of this informations helps.
Happy Holidays!
SBC