There are many different types of Bonsai trees to choose from and actually any plant that has branches and a trunk can be formed into a Bonsai.
Evergreen Bonsai - These types can be grown indoors during the winter and placed outside in a shady area the rest of the year when there is no danger of frost. Some good choices are juniper which are popular for its' windswept look, Japanese Boxwood, Holly Pine.
Deciduous Bonsai - This type of tree lose their leaves in the winter when they're dormant, but what's so exciting about this type of Bonsai tree is they change their leaf colors throughout the seasons. Apricot, Crabapple, Ginkgo, Hornbeam, Larch, Maple, Spirea as well as most Elm.
Tropical Bonsai - A popular choice because many of them grow flowers, these plants can be grown as a house plant year round. Tropical Bonsai include Fig, Bougainvillea, Azalea and Fuchsia. 
Bonsai trees come in many different styles as well, including the windswept Bonsai Plant, the upright tree, as well as the cascade and forest styles of Bonsai Plants.
