We are getting ready to host an R bootcamp this summer at work and I am looking at building on materials that already exist. I just wanted to list a few here while I figure out the best ways to incorporate them. 

Video Tutorials:

This is a fairly new resource, but now contains over 60 instructional videos that are two minutes or less for how to do basic tasks in R. An excellent reference and place to start.

http://www.twotorials.com/

R Tutorials:

Pairach Piboonrungroj has put together an excellent compliation of R introductory tutorials from universities around the world. Lots of great material.

http://pairach.com/2012/02/26/r-tutorials-from-universities-around-the-world/

R Tips and Tricks:

This is a great resource for how to do some basic tasks that can be incredibly frustrating in R.

http://pj.freefaculty.org/R/Rtips.html

R Compared to SPSS/SAS:

For users coming from other statistical packages this reference is a great point in the right direction for how to do familiar things in R.

http://r4stats.com/add-ons

Stay tuned for the further development of my R tutorial for education data–developing on GitHub:

https://github.com/jknowles/r_tutorial_ed