If you are looking for the company that provides you the services like printing the personalised birthday or Christmas cards, the best place to visit is the HGA. This London based company is one of the leading print, design and production companies in the U.K. They print the high quality colour cards on both the sides on the high quality card of your choice. They also supply free envelopes along with the cards. They offer two standard sizes of greeting cards; A5 and A6.