What size and format image do you need to make me a table in the size I want?

For us it has to be 150dpi or higher to keep a good quality product, some people will stoop lower, but not us. (That’s 600 pixels per 100mm run of table).
For example: if you want the table 1000mm x 500mm, the image has to be 6000 pixels by 3000 pixels.
Obviously vector based images are fine as they are infinitely scalable but If you are looking for royalty free images on google, Selecting 8MP or higher would be the best place to start, but the bigger the better really.

Copyright and Trademarks of images used in the making of tables and fridge fronts for clients. 

The client is solely responsible for the contents of transferred image data and for any client approved artwork supplied by chippysworkshop.co.uk. We assume that the client possesses the necessary copyrights, trademark rights or other rights for all works, files and images that are transferred or client approved. In case of infringement of those rights, the client is obligated to indemnify chippysworkshop.co.uk from any claims that might be issued by third parties. This is strictly ensured by liability assumption versus the claimant. If the claimant does not approve the liability assumption the client will indemnify chipysworkshop.co.uk from all claims. In this case the client will support chippysworkshop.co.uk in the defence of such claims. The client bears all incidental expenses (e.g. court and legal costs, fines, etc.). Any purchase on this website confirms the clients obligations in this matter. 

Image content and the law. 

The customer is liable for the lawfulness of the content sent to us. The customer assures that the contents of the transferred image files comply with the law, with the placement of his/her order. Furthermore chippysworkshop.co.uk has no obligation to deliver services which have the consequence of statutory violations. chippysworkshop.co.uk will report any offence to the police if contents of files sent by the customer violate the the law. Simultaneously chippysworkshop.co.uk has the right to deny any service and to withdraw from the contract. chippysworkshop.co.uk is allowed but not obliged to examine the contents that are uploaded to the site as far as their rightfulness is concerned.