I'm going to give a shot at translating this.

Quote Originally Posted by Lampada View Post
Говорится о времени.
"Говорится о времени" reads to me like "it is talking about time," but Google Translate (sorry, cheating) says "it is a question of time," which makes more sense.
У тебя вчера было достаточно времени подготовиться к экзамену. = Вчера ты имел достаточно времени...?
"You had enough time yesterday to study for the exam. = Did you have enough time yesterday...?"

I'd say the subject of the English sentence is "you," but given the other responses in this thread I gather that the subject of the Russian sentence is actually времени? As in "Enough time to finish the exam is near you [У тебя] yesterday"?

The right-hand sides of these examples all seem to use иметь, which my text book says is "not used in the every day sense of possession [but instead] with abstract nouns in a fixed number of expressions." Given this and Throbert's reply, I gather that the use of иметь here, while technically correct, is only for demonstrative purposes here and does not represent normal Russian usage.
Есть ли у тебя сейчас время (помочь мне с моим заданием)? = Имеется ли у тебя сейчас время...?
"Do you have time now (to help me with my task)? = Do you have time now...?" So, just as it appears, the left side and the right side translate to roughly the same phrases in English?

I do not understand what имеется means here. I assume that's third person singular reflexive. Is it just a rule that "Имеется ли...?" means something like "Is there...?"
Будет ли у тебя свободное время завтра? Мне нужна твоя помощь. = Будешь ли ты иметь свободное время завтра?
"Will you have free time tomorrow? I need your help. = Will you have free time tomorrow?" Throbert confirms that время is the subject on the left and ты is the subject on the left. This makes sense--I'm just going to have to keep drilling it until I can remember it!

Thanks much to Lampada, it-ogo, Throbert, and everyone else whose replies I have yet to read through. These explanations are much more clear than what was in the book I'm studying from.