exif/iptc tags

I have been using cam2pc for many years now and have built a large library of images. Now that things are getting out of hand, I would like to start tagging my photos. I have seen how cam2pc uses the tagging feature, however I know that will not be adequate for me.
What I am looking for is a way to build a database of tags, such as names, places, events, etc, and be able to select a group of photos, then select the tags that apply to those tags. What this would enable is to be sure that the tags are always spelled correctly so that when I search for a persons name, a place, a birthday, etc. I can find them easily.
Does anyone know of a utility that may do this, or could this be integrated into cam2pc to make it the ultimate organization tool?
regards,
Scott
What I am looking for is a way to build a database of tags, such as names, places, events, etc, and be able to select a group of photos, then select the tags that apply to those tags. What this would enable is to be sure that the tags are always spelled correctly so that when I search for a persons name, a place, a birthday, etc. I can find them easily.
Does anyone know of a utility that may do this, or could this be integrated into cam2pc to make it the ultimate organization tool?
regards,
Scott