Beets, Mangos, Banana, Plantains, Rutabagas, Parsnips, Figs, Pineapple, Sweet Potato, Squash, Melon, Berries, Carrots, Tomato, Apples, Peaches, grapefruit, oranges, .....
Just ate a mango roasted beet salad, delish! On to my grass fed basil tomato meat loaf :)
White potatoes and other tubers (sweet potatoes, yucca, whatever starchy vegetable you want) Not everyone feels best eating many carbs but if you do those are all good choices. White rice isn't terrible either.
Any food originally from a plant (other than refined oils) will contain some carbs. Fruit will have considerably more than most vegetables, other than the starchy tubers and roots. Nuts will have a small amount also. A few animal foods such as liver and eggs contain modest amounts of carbs. (Oops, forgot to mention a potentially huge animal carb source - dairy other than heavy whipping cream and butter) How much carb you eat will depend a lot on whether you need to lose weight, any health issues, physical activity etc.
Added: A good guide to the amount of carbs to eat is here: http://www.marksdailyapple.com/the-primal-carbohydrate-continuum/
Carb intake here varies here from "Zero-carb" to athletes often eat sweet potatoes after heavy workouts to those who eat rice. Rice is not a paleo food, and generally there are fewer people here who eat rice even than those of us who eat some dairy. Rice is considered a "safe starch" by those who follow the Perfect Health Diet, but even the PHD recommends very much lower intake for diabetics, over weight, insulin insensitive etc.
Yet more - For instance, I eat low carb, typically @40 grams per day because of weight and health. Most of my carbs to keep the number that low come from non-starchy vegetables - mostly greens - small amounts of full fat dairy (lots of people here don't eat dairy) and small treats of berries.
you probably already knew all this, but you're concerned that the amount of carbs from produce compared to traditional SAD sources just doesn't compare, right? As someone trying to gain weight, this makes me wonder what to do about it.