You can find the Powerbooks and Tablebases under the chess engine tab.
Below is an overview of the differences between the Chessbase 13 packages. If you do not know, the Mega Package is a safe choice. Correspondence players and ambitious amateurs benefit from the Premium Package. The Starter Package is a budget friendly way to start.
|Chessbase 13||Premium package||Mega package||Starter package|
|Access to Chessbase Cloud and Chessbase Online Database (over 7 million games)||yes||yes||yes|
|Games download||until 31st December 2015||until 31st December 2015||until 31st December 2015|
|Chessbase Magazine||1 year (6 issues)||1 year (6 issues)||½ year (3 issue)|
|Database||Mega 2015 (ca 6 million games, 68,000 annotated)||Mega 2015 (ca 6 million games, 68,000 annotated)||Big 2015 (ca 6 million games, no annotated games)|
|1 year premium membership playchess.com||yes|
|Corr Database 2013||yes|
|Endgame Turbo 4 (4 DVDs with Syzygy tablebases)||yes|