What I've found helps is to not buy snacks. I eat junk if it's available, but if nothing is nearby, then I can't be bothered to go out and purchase it, so I'll eat a grapefruit instead.
Another thing that I have found helps is to order a community supported agriculture (CSA) produce box. A lot of farmers that supply restaurants are losing a lot of business lately, and at least in the Bay Area, many are starting to sell directly to consumers. I'm on a weekly schedule now where every Wednesday I pick up a box of restaurant quality vegetables in SF, and it's pretty fun because a lot of these vegetables are ones I've never even heard of before. It has become a hobby to come up with new types of meals, and it also gives my wife and I a nice break from the monotony to go for our vegetable pickup excursion.