Roast the trimmed and topped head, then cool and squeeze the roasted head. Voila, roasted, minced garlic. Two cups should be about a dozen heads, depending upon variety and head size.
Pizza.
It wouldn't be recommended unless you're looking for a really salty taste. Keep in mind that garlic salt is mostly salt with just some garlic flavor to it. If the recipe calls for salt, you might want to reduce or eliminate it if you're going to use garlic salt in place of garlic. If the recipe doesn't call for salt, garlic salt is probably not the best option.
There is a recipe for Italian Herb Roasted Chicken at http://www.ukfoodies.co.uk
Garlic and chicken go very well together. Here are two excellent recipes to try: allrecipes.com/recipe/garlic-chicken/ or allrecipes.com/recipe/a-good-easy-garlic-chicken/.
You can use either fresh or jarred, it doesn't really matter. I use jarred only if I have no time to chop it myself. Fresh always tastes better, tho!
A good recipe would be oven-roasted asparagus, which can be found here: http://allrecipes.com/recipe/oven-roasted-asparagus/detail.aspx Another good roasted vegetable recipe can also be found here: http://www.food.com/recipe/the-easiest-and-best-oven-roasted-vegetables-98246
Onion salt tastes like "salty onion". Onion powder just tastes like "onion". I use both onion and garlic powder a lot, but have never used either onion salt or garlic salt, so I can use salt independently (control the amount).
Cloves come in all sizes so you can't determine. If I read it in a recipe and only had minced garlic I'd used 2 teaspoons.
try a raw potato to absorb some of the garlic
You can't substitute garlic. It's a cornerstone of cooking. If a recipe calls for garlic and you haven't any, either rush out and get some or suffer a severe lack of flavor. . .Actually, in Indian cooking, garlic is never used. Asafoetida (also known as "hing" is the substitute. As well, with experimentation, one can find all sorts of flavours which simply train our normally "rigid" tastes to like/love something else. There are many folks alergic to garlic, yet they find ways to expand their palates in other ways and, once it's not being eaten for awhile, garlic is not missed nor is there a "severe" lack of flavour.
Take the standard white bread recipe, and when the machine beeps (for adding ingredients) before the final punch down, add two to eight cloves of minced garlic, depending on your taste. Instead of baking the bread in the machine I usually place it in bread pans, let it rise one more time, and bake it in the oven. That way it looks like I made bread, even though the machine did most of the work. You can also add chopped olives for garlic/olive bread.
The usual ingredients in a typical onion soup recipe are onions, lots of vegetable stock, some herbs, garlic, white wine and some butter. I've found a recipe using the above ingredients and it will take about an hour to prepare and cook.