Contact employers right away. Read every advertisement. New items are added daily. Take the employer's stated qualifications with a grain of salt. You may be able to sell him also.
Some ads give little information beyond the name of the job and a phone number to contact.
If the job title is interesting, don't hesitate to call. If you have a resume, include it with your letter. Don't limit yourself to one newspaper. Put a pro-active ad in the local newspaper stating that you want employment. Willing to start at entry level but interested in upward mobility.