Edit in JSFiddle

// preparing a very long Arrey 

var alphabet = 'abcdefghijklmnopqrstuvwxyz';
var alphabetArrey = [];

for (i=0; i<alphabet.length; i++) {
    alphabetArrey.push( alphabet.charAt(i) );
}

var alphabetSymbolsDivided = alphabetArrey.join("\',\'");


// function itself

function find(arrey, value){
    for (var i=0;i<arrey.length;i++){
        if (arrey[i] === value){
            return i;
        }
    }
    return -1;
}

// testing the function

var abc = ['a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z'];

alert( find(abc,'q') );