Best way to add missing emails to a spreadsheet?

I have a decent database now over over 1,000 local restaurants. I have a LOT of excellent information, but one thing they did not provide was email information (preferably the owner's direct email). I have a few ways I could accomplish this, I know there are bots out there that will scour the website (which I do have) for the contact email for you. However I think the problem with that is it will be hard to correctly merge that data back into the spreadsheet in the correct order and so on. Unless there is an application out there that will import my spreadsheet and has spiders for different information.