Lightroom presets enhance or simplify your develop time with your photographs. Here are a few websites for Lightroom presets that (mostly) offer free presets to be used in Lightroom. If you know of any other sites that I have not listed please comment below and I will add the sites you suggest.
Pretty Presets for Lightroom
Lightroom Killer Tips
Ultimate Collection of The Best Adobe Lightroom Presets
get totally rad
Rule of Thirds Photography
Flickr Discussing Presets
Kubota Image Tools
Any suggestions, ideas? Feel free to comment on this article!