I think your original advice was probably sound, the difficulty is taking the first step. The problem is everything is hard until you know it, then all of a sudden it is all very simple and obvious. The trick is realising this. In my experience of OS projects they are crying out for people to do 'stuff' as long as those people are committed. Exactly what you can do will depend upon the project, to start with documentation (tiss dull but it gets your head into the project) is a good way to go.
I would suggest taking a big jump find a project on source forge that interests you and joining their mailing list, offer your services and see what happens.. you may surprise yourself. You have nothing to lose, if you are honest about your experience then no-one can as more.