any good post pregnancy work-out plans?

So my goal is to loose 20lbs before we try for #2. My son is only 4 months old, so I figure I've got about a year and a half to two and a half years to accomplish this (although loosing 10lbs over the next 6-12 months would be great). Any moms out there have any home exercise plans that worked especially well for them? Any books or videos that you found helpful would be great.