Distances between postcodes (please read post for more info)

Hello,

So at the company I work for we use a few scaffold companies and I'm wondering if there's anyway that if I enter a random postcode (UK) it would work out the mileage between each company and then come back with who the cheapest is (this part I know I could maybe use a VLOOKUP formula to work out but working out the mileage I have no clue). I've looked on previous posts and I just can't seem to get it working.

I'm using Excel 2007 hope you guys can help me!

Thank you. - If you need any more details just ask.

Around 20 which is a bit more than a few haha. Reason I want this is because on our computers google maps is really slow and it can take 5-8minutes to get the distances between 3 companies and then the pricing, was hoping if I could implement all that together into a spreadsheet or something it would decrease the time it takes to do the above.

Thanks.