Dear Sir or Madam,
I am writing you in response to the advertisement for the post of computer expert which was published in our local newspaper.
Since finishing my MBA degree from the university of York, I have become particulary interested in economics and now wish to develop my career in that direction.
Working as a computer expert would be the perfect, and very rewarding way to do so.
I think I would be suitable for the job because during my degree I've worked along with several computer experts and now I consider myself one of them.
I would like to have an opportunity to prove myself working in you team and I am available to start immediately.
I would be happy to attend an interview and look forward to hearing from you.