Neil Spencer, 34, was was found guilty in his absence following a trial at Sheffield Crown Court last month for an attempted robbery offence committed in the Rossington area in July last year.
After failing to attend at court, a warrant for his arrest was issued and officers have been carrying out enquiries and looking to trace and arrest him since then.
He is due to be sentenced next week.
Police are now asking anyone who knows where Spencer is, or has spoken to him recently to get in touch. Officers believe he may also have travelled to Hull.
Members of the public are asked not to approach Spencer but instead to call 999 if they see him.
If you have any information as to where he could be, please call 101 or Crimestoppers, anonymously, on 0800 555111, quoting incident number 576 of August 17.