Thanks to TheCollector for this information.
The most obvious place is to buy one, and there are many places on the internet you can do this, e.g. http://www.allposters.com (or http://www.allposters.co.uk ), or http://www.moviemarket.com (or http://www.moviemarket.co.uk ).
You can also get photos, postcards and posters from retail shops like Athena. Another great place to get pictures is from magazines.
If you want to download photos from the internet, the best place I have found for good quality photos is http://www.altavista.com
-If you go there, and click on the IMAGES tab, then choose LARGE in the scroll down "picture size" box on the right of the page. This will ensure only the largest (highest quality) photos are shown.
-Then enter the celebrities name / film in the search box and away you go!!!
You can also do a similar thing via Yahoo and Google, but I have found Altavista to be the best!!! Edit: http://www.dogpile.com/ is also supposed to be good, according to rpbluesman (thanks!)
Unfortunately, not all celebs will sign "anything" you send them. Some are bound by contract only to autograph "approved" pictures, however, if this is the case they will usually send you one of their own.
I have also gone to a second hand shop to get record albums and found them a very low prices and still in good shape, and just send the cover to get signed.
If you have any other places that aren't listed here please tell us.
