Have you tried googling your question? Does the Sharjah Police have a website? That would be the best place to look I think.
--- Sep 22, 2013 ---Ghttp://m.shjpolice.gov.ae/mobile_en/index.aspx--- Sep 22, 2013 ---Police clearance (Good Conduct) Certificate:
Police clearance (Good Conduct) Certificate is an important document which serves as a proof that the person has no criminal record or previously involved in criminal, breach of trust cases or violation of law both in his home country and during his residence in UAE. Both locals and expats are supposed to obtain this certificate.
Conditions and Instructions :
All compulsory fields should be filled in.
Make sure all entered information is correct.
Make sure all required documents are provided.
N.B. For more information please contact CID on Tel. 065631111.
I have read and agreed to all conditions.
--- Sep 22, 2013 ---Copied from their website. It looks as if you may be able to get it via SMS. I didn't read all of it. Take a look at the website.