What has happened to the long a?

I have noticed that whether from here or "afar," people rarely use that vowel sound that I call the long a, the a that in the dictionaries I learned from had a straight line over it to signify that the vowel sound of that syllable sounded the same as its letter name. For instance, the word tail is often pronounced tell, hail is pronounced like the proper name of the bad place, whale is well. Which prompts me to ask, whatever happened to the wh sound? Regretfully, it has just about gone the way of the long a. It is no wonder. When I look on - say - wikipedia for a correct pronunciation, I am at a loss as to what all those odd characters that inform the reader how to properly speak a word, name or expression mean. Maybe other people do know, or maybe they haven't noticed. However I do pay attention to details of speech, or should I say detells?