It's rare for CL postgrad students to start with a really good understanding of statistics. Here's some places to get help.
John Goldsmith wrote a nice introductory tutorial titled Probability for Linguists
Kevin Knight wrote a very gentle introduction to Bayesian methods for NLP
Getting started with R
The attachments to this page (Rnotes.txt, script.Rnw and data.csv) contain notes on getting started with R and combining R with LaTeX, from the CLT seminar 31 Oct 2011.