http://www.whitespace11.com/drop-in-life-drawing.php) and have been going every Thursday evening. 5 mins from work and with a bus that takes me straight home accross the road it couldn't be more ideal. It's been great to get back to it because no matter how much you study in a sketchbook at home, nothing replaces drawing from life.
Not too much to show for my efforts from that just yet but hopefully it won't be long. I've found that my ability to look and see what I'm looking at (muscles, landmarks etc) is a lot better but my ability with materials such as charcoal needs a bit of practice. I think my main issue is hesitation and lack of knowledge, confidence unfortunately plays a big part in good drawing.
The only downside would be that the class is only 2 hours but it's enough and it lets me figure out what areas I need to work on and then I can come back the next week and try again. It is fairly quiet too compared to the Sunday class; I have always been more relaxed in an empty class than a full one- being relaxed is pretty important for drawing imo.