Definitely time for the International Phonetic Alphabet!
Here are a couple soundboards I found. They aren't great, and one of them is definitely just for General American English, but it's a start.
easypronunciation.com
Here are a couple soundboards I found. They aren't great, and one of them is definitely just for General American English, but it's a start.
IPA Chart
www.ipachart.com
International Phonetic Alphabet for American English — IPA Chart
Find examples of American English words for each sound of the American English language. Watch a video with a native speaker pronouncing each word.