I have just encountered some R PDF books that seem quite interesting. One of them is written by Venables himself.
- The Art of R Programming by Norman Matloff
- An Introduction to R by W.N. Venables and D. M. Smith
- The R Inferno by Patrick Burns
- The R Guide by W. J. Owen
- R for Beginners by Emmanuel Paradis
Do you have any other suggestions I should add to the list?