Kharkov is easily accessible by plane or by train.
The Kharkov city has an international airport, which is connected with international airports of Kiev, Wiena and Istanbul with the regular flights.
It takes 4.5 hours to travel by direct daily IC train (three times a day) and about 8 hours by night train from Kiev. The schedule of trains can be found on Ukrzaliznytsia official site.
The meeting and the accompaniment will be provided for the participants from the foreign countries on request.
If you will need VISA to enter Ukraine the invitation letter will be sent on request. However, Citizens of the USA, Canada and the most of European countries require NO VISA to enter Ukraine (details here)