Usually, spiderwebs are extremely plentiful so there is no problem in finding them. In fact, staying out of the ubiquitous webs is more often the problem. The best places to find webs that are well-suited to photography are grassy fields with small bushes in them. Spiders often attach their web between a bush and the nearby grass. The result is a well-elevated web that's easy to isolate from the background.
Dragonflies are medium to large flying insects.
Evenings find most dragonflies roosting in the low grass and bushes of meadows that border ponds. It is very important to have ponds in the area because dragonflies spend most of their lives as nymphs under the water. When it is time for them to become adults, they emerge from the pond by climbing aquatic plants, shed their exoskeleton, dry their wings and fly away. But, they usually stay in the immediate vicinity of the pond. During late summer and early fall, it is not unusual to find as many as one dragonfly per square yard in the proper habitat.