Point-Based Graphics will be held at the same location as the Eurographics 2007 conference, at the campus of the Czech Technical University
(Faculty of Electrical Engineering). The address is Technická 2, 16627 Prague 6, the room number for PBG07 is 136.
Please see here for a map (the localtion is "C") and for more information on the conference venue.
The conference venue (CVUT) can be reached from downtown by Metro A, exit Dejvicka station.
From the airport it can be reached via the bus 119, again exit Dejvicka station.
Here is some information on public transport in Prague.