Greenhawke:

When you can't find something, highlight it in the instance panel and use 'edit>send to origin' to move the highlighted object to the origin of your current instance.  this is frequently helpful if you drop something into a scene and then can't see it.

Also, you can simply hit the number 0 key to move your camera directly to your selected object.

This has helped me find something many a time with a large scene.

Klebnor

Lotus 123 ~ S-Render ~ OS/2 WARP ~ IBM 8088 / 4.77 Mhz ~ Hercules Ultima graphics, Hitachi 10 MB HDD, 64K RAM, 12 in diagonal CRT Monitor (16 colors / 60 Hz refresh rate), 240 Watt PS, Dual 1.44 MB Floppies, 2 button mouse input device.  Beige horizontal case.  I don't display my unit.