Clip Art: Flora
The Clipart Wizard: Flora - An extensive listing of links to online sources of clipart images on plants, trees, flowers, leaves, gardening, farming.
Flora e Fauna Australiana - A very large collection of clipart and photos of Australian flora.
Homes and Gardens - Free Pictures - FreeFoto.Com - Pictures of various species of flower.
Image Gallery - From the USDA Agricultural Research Service - A collection of photos of plants, flowers, crops, etc.
Plants Icons - Icon sized graphics of a variety of acorns, trees, flowers, leaves, plants, shrubs...
Leaves - from Blaikiewell.com - Maple leaves in various colours.