I really don't understand why they would do this. English voice-overs not only corrupt the original game experience and setting, but they are unimportant and slightly annoying to the people who will actually be picking up Yakuza 3.
If you guys have any specific questions about the story or puzzles, let me know. I didn't really want to get into that stuff in the OP as it may contain spoilers. Hell, if you guys need help, I can do that too.