You may find general information about Istanbul from the following web page:
Turkey demands an official entry visa from citizens of several countries. In certain cases, the visa can be obtained upon arrival at Ataturk airport for a small fee. Before your departure to Turkey it is better to check with a Turkish consulate in your country to determine the visa conditions to which you are confronted.
You can also get information from the web site of Turkish Ministry of Foreign Affairs at http://www.disisleri.gov.tr. The relevant information can be found in the English version of the site at the ConsularInformation / ForForeigners / VisaInformation / VisaInformationForForeigners subsection.
The monetary unit is the New Turkish Lira (YTL). In Istanbul, traveler's checks are rarely accepted. ATMs which accept international credit or bank cards can be found in almost every corner - a strip of logos is usually displayed above the ATM. Almost all ATMs have a language key to enable you to read the instructions in English.
The electrical current in Turkey is 220 volts, 50 cycles alternating current (AC); wall outlets take Continental-type plugs, with two or three round prongs.
The value-added tax, here called KDV, is 18%. Hotels typically combine it with a service charge of 10% to 15%, and restaurants usually add a 15% service charge. Value-added tax is nearly always included in quoted prices. Certain shops are authorized to refund the tax (ask).
PHONE AND INTERNET
The conference hotel is equipped with wireless internet access in all public areas. Moreover, there are public phones and several internet cafes at the neighborhood of the hotel