I find it almost impossible to find volunteer opportunities. I'm a very experienced IT professional and a strong programmer in several languages, and yet so far, I have been unable to find a business (or charity) that will allow me to donate my time as a SAS programmer. I've been on the other side of the table, reviewing applications of interns, and I understand the reluctance. Free work is not really free when you consider the time you must invest as a manager to supervise the intern, and quite often, the contribution the intern makes is so poor that the the cost in time investment is too high, even though the intern is not charging a salary.
This is intensely frustrating, because I have no doubt I can do a good job and I'm very eager to work as a statistical programmer. I wish you well, but my experience is that finding volunteer opportunities is not at all easy.
John Strong