You will be exchanging stories and personal details, but be careful not to get carried away with the e-mailing. Otherwise nothing will be left to start a talk when you eventually meet and you both will feel awkward. Also be careful about asking too many questions. The person on the line might think that he/she is applying for a job at the FBI.
Treat the e-mailing process like a conversation, not like an interview. Ask only really significant questions, do not bother the person with enquiring private details. When (and if) time come you will be told. At the beginning your investigation might frighten your subject of interest away.
Such questions as "What is your dream vacation" annoy and sound silly. Or rather, this one: If you could meet anyone who could it be? Why ask? It is you who the man/woman wants to date with. Or you are fishing for compliments? What do you want to hear then? That you are the best? But you have been communicating only via e-mail, and in the mean time the answer to this question is veiled in obscurity.
When you are corresponding with people that you meet via the web-personals, it will be good to show some patience towards them. You may be asked something that you have mentioned in your profile. It isn't difficult to answer, is it? There is nothing to be nervous about.
People may respond to a handful of ads but read a heap of profiles. They read them, not memorize them. Do you do the opposite? A thousand apologies, then. So, back to the questions. There is nothing wrong if you answer the question about your whereabouts twice. No reason to bellow: Didn't you read my profile?! Show patience and understanding. If it is hard, consider again: maybe striking up an acquaintance via the internet is not for you.
Once you establish a good rapport with someone you may want the person to e-mail you directly, not via the web-personals. The web-personals account may be concealed at any time, you do not know when the person might do so. With the account concealed you have no chances to reach your addressee through the e-mail server on the web-personals site. Provide an e-mail address created specially to communicate with a web-persona. Don't give you primary e-mail. If things go wrong you won't be bothered.