WM/H is generally on Wednesday nights at Dragon's Lair (don't know about days at 10th Planet, I haven't played there in a long time). if you put a post in the pick-up games sub forum someone will probably be open other days too.
there isn't a specific time to come to learn, just show up Wednesday night and ask anyone for a demo game. or post in the forum asking to set something up to make sure you have someone planning to come and teach. there are a lot of newer players right now, so it's easier to find low point games.