Do you use a noise machine in your baby's room? We purchased the Marpac Sleep Mate after your recommendations, and we've been very happy with it. But if you're in a pinch, Johnson's has a free tool where you can create 30 minutes of white noise.
On the Johnson's website, you can download and learn lullabies, get a customized sleep profile of your child, and our favorite: create your own ambient sleep mix. You just click on the icons and drag them into the box.
Choose from the sounds of vacuum, rain, driving, hearbeat, and more.