post your armory and the person below you will tell you what achievement to go get.
no meta-achievement, except if the person only needs 1 or 2 more to get it.
no moneysinks. asking someone to farm gold just to get some nerdpoints is not exactly the finer thing to do.
keep it (rather) easy. don't ask someone who has not yet even gotten his first naxx achievement to get the algalon25 achievement.
and finally: don't ask for things that require the effort of 9 or 24 other players to get.
If you have any restrictions, post them with your armory. For example, I don't want to do any profession achievements and i don't currently raid so no raid achievements.
http://us.battle.net/wow/en/characte...kyjones/simple