Joomla Component Customizing and few Errors solving

I have Joomla site for Jobseekers. I want to send newsletter by creating a customized search from the jobseekers table. I have jnew component. I need to add some more functionality like searching a jobseeker table based on his country, job specialization, age etc. and create a different mailing Lists on fly from the jnew newsletter component. So i shud be able to search users based on that table and save a list for future newsletters.. Secondly I need to also urgently start with customzing a Cronjob Job Alert script(PHP)...I mean I need to add some more things to the job alert template which a jobseeker receives once any specific job is posted...I need to add like " This are the jobs related to you and display his username/password and let him login into the wbesite.. ( please see attachment file) Thirdly i have memory allocated problem ..which a previous freelancer fixed by increasing the memory_limit in the PHP scripts but i still need to put them in more areas.. Budget is low..so bid wisely. Thanks