if you're looking to bulk, a postworkout shake could include dry oatmeal, milk, a little ice cream, peanut butter, protein powder/weight gainer, and maybe a banana....
be sure to eat six to eight meals throughout a day, and if you're going to eat a pile of high GI carbs(pasta or whatever), then be sure to eat it after you work out..steak, eggs, burger, cheese, pasta, potatoes, chicken are all good foods to bulk on. make sure you get plenty.
do you have a decent training split/program? that's second-most important