Do herbs vary in their degree of flavor?
Yes, they do.  Keep this in mind in how much of the herb to use and when to add it in the cooking process.

Strong herbs are added in the beginning of a recipe.  They benefit from slow simmering.  Use about 1 teaspoon for 6 servings.  Strong or dominant herbs include bay, cardamon, caraway, cinnamon, cloves, curry, ginger, juniper berries, hot peppers, mustard, rosemary, saffron, black sage, and whole spices.

The medium flavored herbs are added towards the end of the recipe in the last 10 to 15 minutes of cooking. Use 1 to 2 teaspoons for six servings. The  herbs in this group are basil, celery seed and leaves, coriander, cumin, dill, fennel, lemon grass, tarragon, garlic, marjoram, mint, oregano, savory, thyme and turmeric.

Delicate flavored herbs are called blending herbs, as they make other flavors work well together.  Add these herbs freely just before serving.  Herbs in the group are salad burnet, chervil, chives and parsley.

When when a recipe calls for dried herbs, what is the ratio of fresh to dried herbs?
The ratio is to use 3 times the amount fresh herb as the amount of dried called for in the recipe.

Where is the proper place to store your dried herbs?
The proper place is in a cool and dark storage area. This will keep your herbs fresh for a longer time.  If, the herb has no smell it is time to discard it. 

When you double a recipe, do you double the herb and spices?  
Usually you do not need to double the herb quantity.  I start with one and half times the original amount.  If tripling a recipe, double the herb quantity.  If the herb flavor is not as intense as you like, increase it.

How do you flavor a sauce that will not be heated at all?
Add the herbs several hours before you are going to serve the sauce.

How do you know which herbs go well with certain foods?
Herbs go well with most foods.  There are some combinations that are particularly good together.

 
Below are come of my favorites.
 

Dried Beans:
allspice, bay, celery, cumin, fennel, garlic, hot peppers, mustard, oregano, parsley, rosemary, sage, savory, thyme

Green Beans:
basil, caraway, clove, dill, marjoram, mint, sage, savory, thyme

Carrots:
anise, basil, chervl, chives, cinnamon, clove, cumin, dill, ginger, marjoram, mint, parsley, sage, savory, tarragon, thyme

Eggplant:
basil, cinnamon, dill, garlic, marjoram, mint, oregano, parsley, sage, savory, thyme

Eggs and Cheese:
basil, chervil, chives, coriander, curry, dill, marjoram, nutmeg, oregano, parsley, sage, savory, thyme

Beef:
basil, bay, caraway, chives, clove, coriander, cumin, garlic, hot peppers, juniper berries, marjoram, oregano, rosemary, sage, savory, tarragon, thyme

Fish:
basil, chives, dill, fennel, garlic, marjoram, mustard, parsley, oregano, tarragon, thyme

Fruit:
anise, cinnamon, basil, cloves, fennel ginger, lemon flavored herbs, mint, nutmeg, scented geraniums, rosemary, sweet cicely, vanilla

Pork:
anise, caraway, cardamom, cloves, coriander, cumin, chives, dill, garlic, ginger, mustard, oregano, parsley, sage, tarragon, thyme

Potatoes:
basil, caraway, chives, coriander, dill, fennel, marjoram, nutmeg, oregano, parsley, rosemary, sage, tarragon, thyme

Poultry:
anise, basil, bay, chives, cinnamon, cumin, curry, dill, garlic, ginger, marjoram, oregano, parsley, rosemary, sage, star anise, savory tarragon, thyme

Rice:
basil, fennel, saffron, tarragon, thyme

Salads:
basil, chives, tarragon, parsley, edible flowers

Spinach:
anise, basil, caraway, chervil, chives, cinnamon, dill, fennel, mustard, nutmeg, poppy seed, rosemary, tarragon, thyme

Squash:
basil, caraway, cardamom, cinnamon, clove, ginger , five spice, marjoram, dill, oregano, rosemary, tarragon, sage, savory, thyme