I use a white-noise machine in my bedroom at home, because my room faces a sometimes noisy street. I have used it for years, and I love it! With mine, you can select different settings (I like the "spring rain" setting, but you can have anything from a heartbeat sound to ocean waves). They cost about $20 at Target - I think the brand name is Homedics. You can set them to make noise for a while and turn themselves off automatically (like using the "sleep" feature on a clock radio, or to run continuously. I let mine run continuously while I'm sleeping. It masks routine sounds very efficiently.
One tip, though - I would recommend that you use it for a while at home BEFORE you leave for your trip. They can take a little getting used to for some people - in fact, I brought one on my last trip to WDW and my roommate said that it took her a few days to get used to it! After a while, though, you don't even notice it.