I forget how I came across it, but I've bookmarked this awesome website. It's a sound mixer that can be used to create custom soundscapes.
There are 4 tracks to mix & you can use a variety of natural and rythmic sound samples.
I've used the mixer to make a virtual version of the audial environment that I experienced relaxing by the bay.
4. Wind in Leaves
^ This is what I'm listening to right now.
There are endless combinations though, & I often use it to make ambient sound in my room while I'm on the computer, napping, or reading.