Amnesia. A website with general information, but I like the list of causes and diagnosis methods.
Like a virgin. An article on sex after amnesia and not amnesia after sex -- like Google seems to think I typed in.
All About Romance: Amnesia in Romance. A rant against stories that romanticize amnesia and shows the bleaker side of the condition.
Brain Injury Research Center. Brain injury is the most common cause of amnesia in fiction, so it only makes sense to research it.
Prosopagnosia (Face Blindness). I remember reading somewhere that a person with severe amnesia could have "face blindness" or the inability to recognize faces.
Welcome to the National Aphasia Association. Aphasia is another complication that could arise with amnesia. There's a certain type called "amnesiac aphasia," but I can't say if it's common in amnesiacs. Still, knowledge is power!
Amnesia at the Movies. A webpage about real life rehabilitation for those with memory problems. It focuses on anterograde amnesia.
A True Story of Amnesia. A woman's personal story about her husband suffering from retrograde and anterograde amnesia.
A Man With Amnesia Reunited With His Wife. An article about a man with dissociative fugue and his wife.
The Mini Mental State Examination (MMSE) A test (this version is from 1999) used to determine dementia, but the questions could determine other memory problems.
I recommend seeing Liz Garbus's documentary Coma because a lot of characters seem to go into comas.
There's a book out there called The Vintage Book of Amnesia by Jonathan Lethem, a collection of short stories dealing with amnesia. I haven't read it, but it could be helpful to know how other authors dealt with the condition.
There's this man named Clive Wearing. He's an extreme case of anterograde (and retrograde?) amnesia, but you can see how someone lives with it.
One last thing! I was watching Dr. Phil the other day and he had on this man named Benjaman. Four years ago, he was found naked and beaten up behind a Burger King and couldn't remember anything about himself. Unknown White Male, anyone?
Sadly, I caught it a little too late, but I did watch the segment on a woman named Holly. Her story was fascinating. She took a date rape drug that put her in a coma and she woke up with amnesia. Here is the transcript.