I'm in the same boat as you bro, in fact I'm starting a bulk diet starting this Monday. Here are some tips i found around the web that might aid and answer your questions:
Eat frequently! -- Make time for 3 large meals and
2-3 hefty snacks every day.
Eat larger than normal portions at meals!
Eat higher calorie foods! -- Choose dried fruit,
starchy vegetables, dense whole grain breads and
cereals, hearty bean soups, nuts...
Add lots of extras to food! -- Dont eat anything
plain.
Add healthy unsaturated fats: olive and canola
oil, nuts, seeds, peanut butter, avocados.
Add healthy carbs and protein: honey, jam,
dried fruit, wheat germ, nonfat dried milk
powder,
soy protein powder.
Make beverages count! -- Drink shakes, milk, juice,
etc. instead of coffee, tea, and diet sodas.
Do resistance exercises! -- Weight training helps
convert the extra calories into muscle rather than flab.
Foods to Choose When You Need More Calories
Breads
Choose hearty, dense breads such as whole wheat, oat bran, pumpernickel, or
rye (as opposed to fluffy white breads). The bigger and more thickly sliced the
better! Spread generously with peanut butter, jam, honey, hummus, or low fat
cream cheese.
Cereals
Choose dense cold cereals such as granola, muesli, Grape-Nuts, Cracklin Oat
Bran, Shredded Wheat n Bran or Wheat Chex (instead of flaked or puffed
cereals). When making oatmeal and other hot cereals, use low fat milk instead
of water. Add extra nuts and dried fruits for flavor.
Vegetables
Starchy vegetables such as potatoes,
peas, corn, carrots, winter squash, and
beets have more calories than watery veggies like broccoli, cauliflower,
zucchini, green beans, and cucumbers.
Fruits
Bananas, pears, apples, pineapple, and all dried fruits (raisins, dates, dried
apricots, etc.) have more calories than watery fruits such as oranges, peaches,
plums, berries, and watermelon. Buy canned fruit packed in heavy syrup,
instead of its own juice, for extra calories.
Soups
Select hearty black bean, lentil, split pea, chili with beans, barley, or
minestrone soups. These soups have more calories and carbohydrates than
brothy chicken, beef, and vegetable types.
NOTE: Creamed soups and chowders are also high-calorie choices, but they
are very high in saturated fat and should be eaten in moderation.
Salads
Rather than filling up on watery lettuce, pile on the garbanzo and kidney beans,
green peas and corn, chopped vegetables, sunflower seeds and chopped
walnuts, raisins, cottage cheese, lean meats, tuna fish, and croutons. Top with
a liberal amount of vinegar and oil type dressing.
NOTE: Creamy dressings are high in calories, but also high in saturated fat.
Good luck bro, hopefully this helps you a bit and also look around for a good workout routine, these guys know their stuff. EAT BIG and
BIG. cant go wrong with that.
Quit your jibber jabber. If i ever see you actin like a crazy fool again, your gunna meet my freind PAIN!!! 
