Hi Evan,
I'm glad it's working for you.
If I understand what you're looking for, you want to block other ways of dialing "information".
Since you can't put 916155551212 into the dialed digits field in the system speed dial form you have to user ARS. As Wobbly_head_bob mentioned you can set up a specific ARS route that blocks the call or give them an error message. Pretty simple to do as he explained.
Another thing you can do is to set up a specific route that deleted what the user dialed and then dials "goog411" instead. That way the user gets out just fine. You'd do this via the digit mod table.
The one thing I'm not sure of is how to use wild cards. Just haven't done it and I'm still on vacation so I'm not near my notes. Here's what you'd need to do: if someone dial 91XXX5551212 you still want to intercept that call. I'm just not sure how to capture the area code. Perhaps Wobbley_head_bob can jump back in with the answer.
Ralph