Email as sent....to webmaster@coloroasis.com
It appears that none of the wallpaper images available on your site has been uploaded there with the consent of their owner/author.
It is a violation of artists' copyright to copy and/or distribute someone's work/s without specific consent. Posting their names [giving credit] is NOT sufficient and does NOT release you from culpability.
I would strongly suggest you withdraw any and all images uploaded without consent until such time as consent is requested AND granted.
Please do not be confused as to why/how such sites as Wincustomize.com [from which many of these images appear to have been taken] or Deviantart.com, etc. appear to be doing similar. The images uploaded to those sites are done so specifically by their owners....at their discretion and under their on-going control. [they can remove them as and when they see fit].
Your apparent methodology will likely expose you to potential litigation at worst and public condemnation at best and is thus highly advisable to address at the soonest opportunity.
Cheers,
Paul Martin
JAFO
Admin Wincustomize.com
[On behalf of all WC site members whose works are involved].