Create a new smart album and call it something like "Find...". I set the conditions to "any text contains" and then several "Keyword contains", but you can set up anything you think you might search in regularly. Leave the fields blank for now and save your new album.
When you want to perform a search, click on your Find album, hit command-I and tab to the field you want to search by. Once you hit enter, your search results appear in the Find album. The nice thing about this is it will also remember your last search until you perform another one.
Not quite the same as searching in iTunes or Address Book, but it works pretty well.

