This Link has sections on how to be mindful at work, at school, at home, and in life. It has wonderful how-to's on mindfulness practice and articles from the thought leaders in the field.
Freemindfulness is a website which gathers resources from a community of mindfulness practitioners. There is a 'free resources' section with mindfulness practices to download.
For those interested in the research and science behind Mindfulness, The American Mindfulness Research Association was founded in 2013 and is a website that brings together the latest research in Mindfulness. The have a monthly research letter that you can subscribe to.
Pocketmindfulness is a perfect starting place for people who want to try mindfulness but don't know where to start. Alfred James has created a website which is easily accessible and makes starting easy and fun.
The UCLA Mindful Awareness Research Center has a web page of free mindfulness mediations to download and try. A great place to start or try new things!!!