Inexpensive flat bristle brushes from hardware stores can create grasses and lines. Onion, orange, grapefruit bags cut up can give a “pineapple” texture. Sponges, toothbrushes (which are also used for spattering by moving your finger along the bristles), mesh screens, and other kinds of screens can create texture. Even using a broken tree stick dunked in paint can give scratchy uneven strokes. Any item that has holes can create textures on dry paper. Items that have indentations, like paper towel designs, work well on wet paper. Go give it a try. And wear a smock.
Happy painting!