In angiosperms, flowering plants, they're in the flower; it has the style, stigma, filaments, and ovaries. The flower is not always obvious, such as in wind pollinated plants like willows and ragweeds.
In gymnosperms, like pine trees, they're on the cones or cone-like structures.
In non-seed vascular plants, like ferns, club-mosses, etc, they reproduce primarily by spore which occurs in various places.
In bryophytes, non-vascular plants, they also reproduce by spores, usually growing a separate body part, the sporangium, which releases the spores.
Then there's the green algae, water plants which do not reproduce sexually like the land plants do.
In all these groups, there are examples of vegetative reproduction, reproduction without sex, which is not located in the same places as sexual. Many plants will grow roots and form a new individual with the same genetic material of the mother (this is called cloning) if one cuts a piece and puts it in water, or even just soil. Some plants, such as strawberries, reproduce sexually by producing stolons, also known as runners, which travel along the ground (either on top or under) which can root and form new clones.