Hello Mr. Cha, and welcome back to Just Answer.
I am fine, and hope this finds you well!
My name is XXXXX XXXXX I have been a foreign language teacher and have also taught English as a Second Language to school-aged students and adults for many years. One of the best ways to improve your American accent is to try to speak English only, with friends, co-workers, etc., so you can practice as much as possible, and also ask your friends to correct your pronunciation, when needed. The more you hear and speak English, the better your accent will become. Also, watching television programs in English and listening to the radio, will be helpful.
I think you have not yet found any teachers, cd's, videos or dvd's to suit your needs, because you would like to practice only 'conversational' English and I have a feeling from your description of your past experiences, that people are trying to teach you the rules of grammar, spelling and usage, which in English is quite complicated. Yes, it is best to learn these rules and employ them in your writing and speaking, but when you're present goal is to lessen your Korean accent, you need as much conversational practice as possible.
I do not speak Korean, but in every language, there are certain sounds that either do not exist and/or are not pronounced in English. This is what causes you to retain your Korean 'accent' when speaking English.
You can look for something like this, in your Public Library:http://www.phoenixpubliclibrary.org/record.jsp?R=75602#
This sounds perfect for your purposes, but it is more costly than $15. I don't think you will find what you need if you are limited to that amount.http://accent-master-software-and-training.amazonwebstore.com/English-Pronunciation-Made-Easy-for-Korean/M/B002CFIVV6.htm?traffic_src=froogle&utm_medium=organic&utm_source=froogle
Try to find out if there are Continuing Education classes given at your local High School or Community School, and sign up for a conversational English class. You might not need the beginning level, as you are already quite fluent, so perhaps an 'intermediate' class will be better for you. If you explain to the teacher what you are looking to accomplish, hopefully the class will be geared toward improving/perfecting your American English pronunciation.
You can also find a private tutor in your area that gives individual or group lessons in conversational English, and in this way you will have the benefit of personal attention and the opportunity to interact and practice your English with others.
I wish you much good luck, Mr. Cha!
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