Getting closer to a surgery date and have some questions

I just found out my preop date (3/7/12) and am still waiting for my actual surgery date for my bypass. I am so excited and just a little nervous.
 
So far the only people that know are my husband and 2 friends and they all give me the usual you look great speech, you don't need it. So tired of hearing that. I am 5'11" and weigh 300lbs. Back when I felt normal my highest weight was 175. My goal weight is 150

How soon after surgery is the best time to begin working out? What are your favorite tips you can share? I'm not planning it, but has anyone gotten pregnant post surgery? How soon and how did you handle it?

Any tips or advice you can share would be great.