The station names of all stops in Vienna start with its German name "Wien". This is internationally recognized and helpful for buying tickets. The railways are managed by the ÖBB (Austrian Federal Railways). Read more about train travel within Austria and reaching Austria by train.
It can be puzzling to understanding where trains depart and arrive, i.e. trains heading East often leave from West Station. It is best to check the scheduals online and plug in the exact train, subway or tram stop you are going to/departing from, this will give you the quickest solution. Railway agents are likely to give you an easy answer where the most train to somewhere leave from, you may not be told about certain trains that don't fit the regular pattern.
Ticket offices are noramlly open during all departure hours at Wien Meidling and Wien West (around 5AM-11PM). It has come to light that with more trains leaving from stations like Wien Praterstern, trains depart outside of ticket office hours. If this is the case you can buy the ticket on-board from the conductor, they are only able to sell regular as well as certain discounted tickets (cash only), so it is best to buy ahead if possible.