Yes I'm going through it as we speak.
The current circuit I've been using is this one:
Building an Electrocardiograph I | Skippy Records.
But it hasn't been working..
The problem is I'm trying to avoid buying new components (as I have quite a few bits and pieces already!).
I've got a bunch of 741 (which are probably far from being the best opamps for this application), and would like to use them up!