Every one of my Canon lenses has a small switch to allow for manual focusing. As far as which lenses fit which cameras, any lens marked 'EOS' will fit the Rebel line of cameras as long as it is not made specificaly for the digital camera bodies (bears the 'EF-S' designation rather than just 'EF') unless they have changed it since I bought a new lens. Any reputable camera shop will be able to ensure that you get the proper lens for the camera body you choose.

Lenses now days are mostly zooms that cover from focal length A to focal length B, for example 80mm to 200mm. Most Canon bodies come with a standard range zoom lens which should be fine for your purposes. I would suggest something on the order of either 28mm-80mm or 80mm-200mm, either of which should be a standard option if you buy the kit (i.e. camera and lens combo). Hope this helps.

- Randy