Note that in the following tables, there is nothing new; long and short vowel sounds, the circumflex, etc. are used in the historically accurate sense. I have spent an inordinate amount of time on this page, but in the final analysis you will need to learn it for yourselves. It will be time well spent. My usual resources are:
If you are having trouble viewing this, in any browser you can incrementally increase the font size by holding down the <Ctrl> key while repeatedly typing the "+" key on the numeric key pad; (if you use the one on the numeric key pad you won't need to use <shift> "+"). To incrementally decrease the font size it is <Ctrl> "-". To return to the default size type <Ctrl> "0" (that's zero, not capital "O" as in "Off").
Note please that this is by no means a complete list, but rather is all of the accent markings required to match the the pronunciation keys found in older K.J.V. 1611 Bibles. My intention is to restore what has been removed in these latter days by those who do not tremble at the Word of God (Isaiah 66:2).
Another problem is that we are in a constant state of change in the protocol that defines these symbols; The standards are not finished and the same symbol in different languages is enunciated differently. Despite all this there are enough diacritical marks and symbols to accent the nouns in the K.J.V. Bible of 1611, and that is the goal on this site.
Sometimes (and perhaps frequently) when a symbol does not display correctly it could be because there is no font on your system to render that letter/symbol in the language for which it is defined. For example, a majority of unusual [in the English language] symbols are defined in Latin font sets; you probably have some Latin fonts on your system, but you may not have one for the symbol you are not seeing correctly. This is likely to be temporary; the number of free fonts available for installation (which are being used in popular browsers) is increasing.
Regarding the circumflex consider this dictionary definition: circumflex: definition 2 of 2 noun: a mark ˆ, ⌢, or ˜ originally used in Greek over long vowels to indicate a rising-falling tone; and in other languages to mark length, contraction, or a particular vowel quality. The circumflex combining the 2 letters "oi", as o᷍i is pronounced "oi" as in "oil".
Regarding the umlaut (2 dots over a letter): it is primarily from the German language which, unfortunately, I do not speak. However, I do have access to language teachers and will try, as time permits, to update this page to aid those with a desire to learn how to pronounce the nouns applying to persons and places in the Bible correctly. For now, place the tip of the tongue against the back of the upper teeth when pronouncing the drop down tip which appears when you hover over the letter with your mouse.
Regarding underlined 'ch': A common accent in Scripture is the underlined letters "ch" (in any letter case) i.e. ch which means to be pronounced as "ch" in character. For example: Nĕb-ū-chăd-nĕz´-zär king of Babylon. I will add to this page as needed and as time allows.
Ē-zēk´-ịĕl 9:4 And the LORD said unto him, Go through the midst of the city, through the midst of Jerusalem, and set a mark upon the foreheads of the men that sigh and that cry for all the abominations that be done in the midst thereof.