Hi Len,
I have had 100% success with Chemspecs anti static chemical. I always apply it to clean carpet and ensure that I apply the full recommended qty as per the instructions. From memory it is something like 5 litres (mixed) per 25 sq metres. You will definitely need a good electric sprayer. You will need to treat all walkway areas where people generate static through the friction from their shoes. There is not much point moving furniture etc.
As an alternative you could investigate the internal enviroment in the office. Can the humidity be increased. Static problems mostly occur in a dry atmosphere. Also if the staff are getting shocks in specific places eg. Lifts, entrance doors etc you could consider installing anti static carpet or matting.
I know you are not shy about raiding my web site

so have a look here
http://www.designcare.co.uk/Anti%20static.htmI have never treated an area so large so advice on pricing is tricky. I usually charge 1.50 per sq metre but I suspect this is not realistic on a project of this size.
Good luck
Nigel