44 целых–9 десятков?
First of all, this is called "десятые" (доли), not "десятки". Thus, the phrase "сорок четыре целых девять десятых" is correct, although rather formal. This is something you might hear on the news, and is also how schoolchildren are taught to cite amounts of money.
A more common way of citing figures is to omit the "целых" and "десятых": "сорок четыре и девять миллиарда долларов". This is quite common in speech. (It's not ambiguous, since for "$44 и $9 миллиардов" one would say something like "44 милиарда и 9 миллиардов долларов".)
When the value to the left of the decimal is zero, the word "и" can sometimes also be omitted: "$0.9 млрд" -> "ноль девять миллиардов".
Finally, there's a special case when we have a different, smaller, unit of measure; for example, for meters, we have centimeters, for rubles we have kopecks, etc. In this case, the speaker can implicitly convert the fractional part into these units, and cit it, often omitting these units:
3.2 м -> "три метра двадцать сантиметров", or "три метра двадцать", or even "три двадцать", if the units are obvious (e.g. "высота потолков три двадцать").
3.2 кг -> "три килограмма двести грамм", or "три кило двести", "три двести".
1.2 м -> "метр двадцать"
1.2 кг -> "кило двести"
$1.2 -> "доллар двадцать"
Do russians ever cite quantities like один точка два килограммов мяса instead of один целый два десятка килограммов мяса.
That's somewhat awkward, but you'll be understood (although I'd say "один точка два килограмма", not "килограммов"). It sounds more natural with longer numbers, e.g. 137.035999 -> "сто тридцать семь точка ноль тридцать пять девять девять девять" (inconsistency intended).
Some might tell you you should say "запятая", not "точка", but nowadays both words are actually used, with "точка" IMHO being even more common in the context of IT.
And finally,
один целый два десятка килограммов
The correct way of saying this is "одна целая две десятых килограмма", because "доля" (or "часть") is implied: "одна целая доля две десятых долей килограмма".