Her Majesty's Courts Service does not make such information available online. The only way you might find the information on the internet is to see if the local newspaper's website covered the case. (However, the majority of newspapers only keep their news pages online for a few days).
However, every court has to maintain an official register, which is a public document. This provides a 'bare bones' summary of all matters heard before the court. e.g. "Fred Jones was convicted of the theft of a frozen chicken from Tesco and sentenced to 100 hours community service".
Contact the relevant court to find out how to obtain the information you require:
http://www.hmcourts-service.gov.uk/HMCSCourtFi nder/
Chris