something I struggle with (and I'm a marathoner and meet with nutritionists often, attend boot camps 2x a week and training 2x a week) is that I'm always on "the go", so I can get into ruts where I'm snacking all day too.
But that is OKAY, if you are snacking on the right things. Keep in mind that the more often you eat (not more; more 'often') the harder your metabolism has to work, and the harder it works, the faster it becomes! Just like exercise and building muscle: the more you do it, the faster and stronger you get! Your metabolism is the same way!
So smaller portions of the best things is actually very good for you! Snack all you want!
I struggle with having things ON HAND. So what I try and do is take time on a saturday or sunday and chop all my veggies and fruit for the week and package them up in to-go baggies so I can just grab them from the fridge. I keep a cooler in my car for nuts, fruits and veggie bags to snack on the road in between meetings, school, picking kids up, training etc.
(almonds, peanuts, chopped celery, carrots, peppers, apples, strawberries, grapes, oranges, kiwi, cheese cubes, rice cakes, natural/organic peanut butter, or make tuna salad ahead of time & use celery to dip it in etc)
Also, I find that drinking water from a straw makes it much easier bc I honestly just don't LIKE water but it is SOOOOOOOOO good for you in ways I don't have room to discuss! Get a bottle and drink from a straw all day; you'll be surprised how much water you get in and how full you feel!
a great magazine is Clean Eating which has very simple, easy recipes that are SO SO healthy. They have a cookbook out as well, which isnt too expensive on amazon.com.
http://www.cleaneatingmag.com/