I knew someone with this disease and staying away from added salt and high sodium foods was the best thing he did. He really suffered when he had, for example, lunch meat, which contains a lot of sodium. Soft drinks are a hidden source of sodium, too. Restaurant eating was tough for him so if you like restaurants, it's a good idea to get the nutritional content ahead of time. Most chain restaurants will know the nutritional content of their dishes and you can ask the restaurant, go to their website, or write the corporate headquarters
If giving up salt is a real problem (it would be for me!), try using the Mrs. Dash products or making spicy ethnic recipes.
You can use fitday.com to check how much sodium you're getting, and also to check sodium in foods that don't normally have a label (like eggs, vegies, etc.--probably not a high source of sodium, but it's worth checking).