Lilies: Can you help me ID this?, 0 by Joan

Joan wrote:
I know very little about lilies, and I want to ID this one if I can. I don't know where to even start.

I bought this lily in a pot in May 2004. I gave it to my Mom for her 77th birthday which was 4 days before she passed away. I brought it home and planted it in my garden, not really expecting it to come back. But it did, and today it's blooming. I would love to identify it if possible, or at least figure out what type of lily it is? Seeing it blooming again makes me kind of sad.

Any help or suggestions would be appreciated. Website suggestions would also be great. I can search them, but I don't know of any that have proven accurate information.