It can be a bit complicated because of the rules concerning what case goes with which numbers, but I shall try and explain! Tell me if you need extra explanations because I'm not that great at explaining in text, it's easier in person!!
In Russian you ask (and say) "to me is X years".
This uses the Dative form of the personal pronouns.
The Nominative forms (eg the basic form that we start off with - in English, I, you, him her) of the personal pronouns are as follows:
* Ñ (I) - Ya
* мы (we) - My (the y being a long sound - listen to an audio file of this because it's a diffiult sound to describe. Eee, sort of - but usually transliterated y)
* ты (you - singular) - Ty (to rhyme with мы above)
* вы (you - plural) - vy (same sound again)
* он (he) - on
* онá (she) - ana
* онó (it) - ano
* они (they) - ani (long ee sound for the i)
The acute accent denotes stress - these accents are NOT used in normal written Russian, but often used as a guide in textbooks.
The Dative forms of these are:
Мне - me. - mnye
Тебе - you (informal). tebye
Ему (m), Ему (n), Ей (f) - him, it, her. - yemu, yemu, yey
Ðам - us. - Nam
�'ам - you (formal, or plural). - Vam
Им - im (eem)
The other words you need are "how many?" - Ñколько, (skol'kuh) and the words for year(s) - год, года, лет - god, goda, lyet. (год is the singular form for year, лет is actually a form of the word for summer, in the genitive plural, but don't worry about that too much at the moment!!)
To ask the question, you need your question word - Ñколько - the right preposition - most likely Тебе or �'ам - and the word лет.
Сколько вам лет?
Сколько тебе лет?
To answer you need the appropriate pronoun, Мне, your age (in my case, 29 or двадцать девÑть, and the right one of the three words for years. This is where it gets a little complex I am afraid.
If the name of the number is 1, or ends in 1, you use the nominative form of the word год - ie exactly as it comes.
Russian works pretty much like English in that you have special words for the "teen" numbers, so 11 doesn't end in a spoken 1, but 21, 31, 41 etc do.
If the name of the number ends in 2, 3 or 4, you use года (the plural form). Again, 12-14 behave differently but you use года for 23, 24, 54, 62 and so on.
If the name of the number doesn't end in 1, 2, 3, 4, then you have to use лет.
So, in answer to the question I would say "Мне 29 лет" (Мне двадцать девÑть лет).
And you are 14? so you would say, "Мне 14 лет" (Мне четырнадцать лет)
By the way, those "teen" numbers are easier to remember if 1) you know your numbers

and 2) you realise that четырнадцать literally means "four-on-ten".
Hope this makes sense... please ask if there's anything I can clarify, I don't know how to make it simpler!!
Wow! that's a lot to take in...