you enter in all of the ingredients to sparkrecipes.com
just like you would if you were eating each ingredient separately. weigh the total yield of the recipe, then enter that weight in number of servings. so if your total yield weighed 500 grams, enter in 500 as the serving size. make a note in the serving size that it makes 500 1 gram servings.
if you were stating that it is hard to find some of the ingredients to enter in that have gram measurements, either keep looking through the options or just manually enter the info in front of you with the gram measurements. i find that most options i use have grams as an option from the pull down serving size measurement menu.
-google first. ask questions later.