My recommendation is indeed to use the username and ideally link to their user page.

http://creativecommons.org/licenses/by/3.0/legalcode Sections 4.a./4.b. specify what attribution requirements exist by default.

Since you decided to give gender to the elementals, why not a 50/50 distribution?

Here's a recording of the lines. Hope it will be useful and that you'll share the results on OGA.

http://freesound.org/people/qubodup/sounds/197550/

It'd be curious to know how you edit them as well. I have a bunch of Audacity tutorials, which might or might not be helpful for this task: http://www.youtube.com/playlist?list=PLnmtnFt6ekNVdb2DqNbbkAmHVWXbeShWS

Beautiful minimalistic!

I'm not a stick in the mud but thanks for teaching me that expression.

Here's how I came to the conclusion that use in own products is prohibited:

1. Look at This submission on Sketchup. The only indication of terms is the footer link to sketchup.google.com/3dwarehouse/preview_tos.html. Find a section in this document that permits the users of the Service to use the works outside of the Service. There appears to be none.

2. Look at http://sketchucation.com/forums/viewtopic.php?f=79&t=38857 and http://blenderartists.org/forum/archive/index.php/t-131594.html and copy parts of the text, for example "distribute copies of derivative works" - which seems essential to the interpreation of the users that use outside the services is permitted - and try to find that exact wording on sketchup.google.com/3dwarehouse/preview_tos.html and google.com/intl/en/sketchup/3dwh/tos.html . It seems impossible to find.

Works taken from or based on works from 3D Warehouse can not be released under free licenses without explicit permission by the copyright holders. This also means that they can't be uploaded to OpenGameArt.

Good luck with your project but I advise you to talk to people you trust to interpret a legal document for advice (and not rely on years-old forum posts by strangers).