I have a question for database users. I have just purchased exachess for my mac. Now I would like to extend the already included database of 1300k games.So my questions are the following:

1. Can anyone suggest sites from where I can download (many) games?

2. If I buy megabase 2010 from chessbase, can I use it with exachess? I know that exachess can read .cbf but not .cbh files. However I am still quite unfamiliar with chessbase and chess databases in general and I don't know in which formats the files are in the last chessbase release.

Well you have the option of getting it converted to PGN  ... which is the universal format any application should support.  Then convert the PGN to your exachess format.  Or better yet, find a megabase online that exists in PGN.

 Though with a megabase, this will certainly take time ... but it should be worth the effort.