Nuts, lots of nuts. Great snack.
Almonds (plain) seem to be the best macronutrient-wise. Peanuts and Cashews seem to naturally have more carbohydrate, so I base my 'nut-snacks' around almonds...
My "go-to" veggies are carrots (not too many, they've more natural sugar than some veggies), broccoli and cauliflower - they are nice in a stir-fry/sautee... broccoli and cauliflower are also great with cheese sauces or as part of a casserole with cheese, bacon, etc.
I've personally started trying to get more organic/natural meats: Grass-fed beef, free-range chicken, that sort of thing. I found a nice place to buy nitrate-free bacon... it's more expensive, but worth it IF you can afford it. If not, it's not a deal-breaker - but do your best where you can.
Just don't buy any processed meat. Sausage from your butcher may be OK, but stuff like sausage, hot-dogs, bologna,etc. from mass-produced-processed-meat companies is kinda scary. Stick with real beef, pork, chicken, lamb, etc., wherever possible.
Oh, my new trick is steak with BUTTER. I don't know why I didn't do it before, but it's fantastic to use butter as the oil on your grill, and melt a dollop on top of the steak as it finishes cooking and resting before serving. Nom.
As was said, watch it with fruit - I usually have berries as my fruit - lots of antioxidants, low-GI and lots of fiber. That being said I usually only have 1/4C to 1/2C at a time, max. And generally only once a day. I will also have 1/2 a granny smith apple, and rhubarb as mentioned is good too. (Dip the other half of the apple in lemon juice to prevent it browning, eat it another day).
If you're into baking you may also want some almond flour/almond meal... maybe coconut flour, flax meal, etc. Check out the forum recipe sections to see what you might like, and grab ingredients for it...
I like low-carb pancakes sometimes SLATHERED in butter with some Walden-Farms no-sugar maple syrup and a strip of bacon and a scrambled egg... Great breakfast that seems like carbs, but isn't!