how do i find out which seo company has placed my company on front page of google?

[Mighty Dandean]

How do i find out which seo company has placed us on the front page of google?
I received an email yesterday from WORLDWIDE MARKET SOLUTIONS stating I was required to pay £1495 + VAT for google marketing. But if I paid today they would accept £900.
We accepted the 30 day trial but asked for our days to be not in one block. and requested 5 days to 'test the water'
Apparently they have tried to take £99 +vat each month since August but failed. So they now want the full amount. We gave them our bank details for a 1 off payment.

Our web address does not appear on the google listings at the bottom, just on the top by google maps. How can I find out which company achieved this.

Having googled this WORLDWIDE MARKETING SOLUTIONS. It would appear many people are in the same position.

If anyone can advise me how to find out who puts the company name and loaction on google maps or whether they also have had any runnings with the company i would grately appreciate it.

Cheers