Canon 40D has a Canon EF/EF-S lens mount and currently there are 326 native lenses available for this mount.
Canon 40D doesn't have a sensor based image stabilization system but 112 of these lenses already comes with optical image stabilization.
Since Canon 40D has a APS-C sensor, it has a focal length multiplier of 1.6x so you have to multiply lenses original focal length with this multiplier to find the Full Frame equivalent focal length of the lens when mounted on 40D.
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Canon 40D Lenses with Image Stabilization
Canon 40D Lenses with Weather Sealings