Trevor - don't know if you've seen this yet, but here is an answer from another post: Change the layer you want to select all elements in to the active layer, then click on the button with the eye symbol in the layer window. This makes all other layers at once invisible (except for the background layer). Then you can press CTRL+a and all elements and objects on this particular layer are selected. Personally, I would prefer to have 'layer' as a choice in the 'select by' function, but this gets the job done.
