I lost 20lbs this past fall by doing Couch to 5k. Its a walk/run program that is FABULOUS for those who are out of shape. I am still overweight so I plan on picking back up the running here VERY soon. So far I have done two 5ks (the last one I just ended up walking with Max... but hey I did another one!).
Cool Running :: running run training marathon runners jogging jogger joggers runner run fitness exercise diet weight loss nut... is the website and there are podcasts that you can download for free to let you know when to run and walk.
One recommendation is to drink LOTS of water, cut back on soda, and have healthy snacks around the house. Look up new recipes. Switch to whole grains, cook more vegs, proteins, and try to restrict the amount of carbs you eat (and keep them complex). If I want cookies or something, I just grab a "100 calories" pack. I have a TON of those in the house so I am not tempted to buy a huge bag of cookies.
Also, whenever you have free time (while at work, watching tv (commercials), cooking), throw in a few jump and jacks, push ups, sit ups, etc. You would be amazed how much you can randomly throw in your day and how many calories you can burn!
Hope that helps!