The nice thing for internet is people share and distribute data everywhere, but sometimes, it's annoying that people steals your works without quoting where it comes from. There are a couple of things you can do:
(a) I like to put a watermark on the pictures I took, I used to do it one by one with the image editing software. Until recently, I found a FREE software called TSR Watermark Image Software. It can do all pictures in a folder at once and it's freeeee. Highly recommended.
