One of the things to bear in mind is the lack of edible plants in any one area. There is no point in searching for something that either does not exist, or there is not much of in your area. This is more important if you are having to forage for your food, because you can not afford to expend more energy looking, than you can replace by finding. You need to keep an open mind to all types of foods available, not just flora, but also fauna.
The following are the most common and most easily found plants in my area.
Appleberry. Small fruit growing on a climbing vine.
Spike Rush bulbs. This plant grows in water. The bulbs are not very tasty or even pleasant raw, but I have not tried cooking them.
Mistletoe Berries. Not very large fruit, but there is usually a lot of them on one plant. This plant feeds off trees. The seeds are sown on the branches of a tree by the Mistletoe Bird. More often found growing out of reach, but occasionally can be found like this one growing low to the ground.
Nettles. Care must be taken harvesting this leafy plant, as the fine hairs on the leaves will sting. Boiled I find they remind me of spinach or silverbeet.
Cumbungi. Flour made from the pollen is usefull, new green shoots are tasty raw. The new flower heads can be cooked like corn. The roots contain a good deal of starch, which can be collected by soaking in water after breaking, then evaporating the water. Or you can chew on the roots. Again, these can be found in water.
Grass Tree/kangaroo Tail/Black Boy. This plant grows Australia wide. The base of the narrow leaves can be eaten. The amount on each leaf is minimal, but there are a lot of leaves. The flower stem can be used for carrying fire, & for producing tinder for fire lighting. It can be used for making fire by the hand-drill and the fire-bow methods. The stem can also be used as a spear shaft if you add a hardwood tip. The flowers can be sucked on for the nectar, or they can be soaked in water for a refreshing drink.