You can use Look-at in the view menu (on top of the 3d window) but you probably want 'fit' - press f. This will center the view around what you have selected. Adjust the view center with the middle mouse button and dragging.
SL doesn't (yet) support polygon objects. You'll need to look into sculpties - probably best to search on here and look at the Inivis page
http://www.inivis.com/secondlifesculpted.html. The texture mapping
is important for it to work, so it's best to start with the sample SL objects that come with AC3D.