Lecture notes for both the talks by John Cremona and Nils Skoruppa. (Thanks to Laura Peskin for providing them).
The exercises were typed up by Jitendra Bajpai.
Hendrik Bachmann has provided an implementation of "Number theorist's Sudoku", which allows you to solve them interactively.
Lecture notes by Jan Bruinier.
Lecture notes by Richard Hill.
Lecture notes for Don Zagier talk, typed by Martin Raum. You are invited to improve the tex-file and send them back to me.
Lecture notes by Cris poor are not yet available.