QUOTE(piskie @ Mar 9 2011, 03:34 PM)

And all this is further twisted by such things as Dynamically assigned IP and search history of "You" built up by Google using various methods. For instance, what if any BHOs do you have.
I thought that too. I turned off the personalised search setting with the "&pws=0", though I am not sure how much that helps...
What do you mean by BHOs by the way?
QUOTE
If he really did something to change your rankings and he didn't have access to the site itself, then he must have pointed a bunch of links at you, probably using "lawn sign" as the anchor text of many, if not all of those links.
If you check Yahoo Site Explorer for links to your site from domains other than yours, you'll see that quite a few of them are coming from the site of a basement waterproofing company. According to the WayBack Machine, those links weren't present 10 months ago.
You're also linked to from Wikipedia's page on lawn signs, and it looks like that link was added in late January.
I don't know if the person you spoke with controls these links, and I can't tell you exactly how long most of them have been in place, but that's all I can think of if he really did affect your rankings.
By the way, your site comes up at #1 for me when I search for [lawn sign toronto]. If I drop the city name from the query, you're not in the top 10 for me.
The search query we rank low in is "lawn sign".
The thing is, our position for that keyword went from 4th page, to first page, to fourth page, all in about 24 hours. How is that even possible??