I'm working on a project at work to download imagery from else where and add it to geoserver. I have no experience in GIS, nonetheless geoserver. I've been hunting through the REST api for 2.0.X of Geoserver and can create workspaces and empty coverage stores. I get that coverage stores hold raster graphics, but is it one-to-one or do they share a special relation by being in the same store? What's the URL and method (PUT, POST, etc) to add a tiff to a coverage store?
Well the model for raster data in geoserver is that a coverage store can contain multiple coverages. But that said in general, in that 2.0.x version the relationship is 1-1. There is currently work going to support coverages that have the notion of another dimension (like time), at which time you will start to see geoserver support multiple coverages for a single coverage store.
Mapperz provided a good link with some examples. There is also a good reference in the user guide:
It is for shapefile but for geotiff it is more or less the same, just change shp -> geotiff accordingly, as the examples show.