Uhm if you've saved it as a psd (or a tiff) you have an alpha channel and therefore a transparent background :) In photoshop, go to Select -> Load Selection -> Alpha channel and there you og, your character is now selected. You can invert the selection to select only the background and then delete it. Remember to promote the background layer to a full layer or it won't be transparent :o)

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You just can't put the words "Poserites" and "happy" in the same sentence - didn't you know that? LaurieA
  Using Poser since 2002. Currently at Version 11.1 - Win 10.