ok im confused about a lot of stuff with the lock considering talent builds just tlaents etc. i am still trying to decide where to go and what to do with them. a lot of people are telling me go with demonology...i have 2 friends...one is a tank and another is a healer...what talent build should i do to fit right in for dungeons etc

what level are you and are you looking for a levelling build or a level 70 build?
if you're level 70 and grouping what stats do you have on your gear (roughly) and do you plan on raiding at all or just 5mans/heroics?

heroics u looking 4 a demonology man but for 25+ man raids then go afflic cause the damage builds up over time on the boss and if u kara become destro

oh my god. ignore that man

the damage output is based on gear and gear is based on progression.
affliction is much more forgiving when you have low amounts of +hit on your gear so affliction up to UA and filling up on destro will give you the best damage right through to kara.
felguard raiding only become truly viable when you have the T5 2 piece set bonus which heals your pet but by the time you're at T5 content you may well have the stats required to go destuction anyway, in which case you're likely to benefit most from a destruction build.
min stats for destro:
202 spell hit
1200 spell/shadow damage
22% crit

if you're only going to do heroics then you don't need to worry about hitting 202 spell hit but the other stats remain important

ok this is how i went, 45/5/11 is great until you have 900 bonus damage.

once you either have already, or are able to run raids, that drop crit gear, go 0/21/40. 

raiding as demon is nice for 700-900 spell dam, go 20/41/0, nightfall and 3/3 empowered corruption. 

felguard and afflition specs are also great in pvp.

a strictly pvp destro build would be 0/5/56 or 0/8/53 etc. until you get 3/3 demonic aegis and the fel stam., so 0/13/48 or 0/16/45.  out of those i did best in arena with 0/5/56, you can burn pallys with confalg beforethey dispell immo.

hope that helps.
Rogras 70 orc warlock (45/5/11) eonar