Good question, Mike!
I'd spread them out so the birds can choose their favorite spot. I wouldn't put them too near your feeders so they don't get filled up with sunflower hulls and other schmutz. And relatively close to shrubs is ok so they have a place to perch and dry off, but not so close that the neighborhood cat can jump out and grab them.
And, enjoy the show! It's amazing to me how many birds can splash around in there and line up around the edge waiting their turn. I get quite a kick watching them frolic away.
Community hostess, wildlife gardener, avid birder, loves butterflies and all other critters. Find me on Twitter @CB4wildlife