ICOM's Thematic File on Tax Incentives has resources from a number of countries and an excellent bibliography. Contents as at August 2007:
The Taxing Aspect of Donations
by David A. Walden Secretary-General Canadian Commission for UNESCO
From Fine Art to Fossils: Canadian Museums
by David A. Walden Secretary-General, Canadian Commission for UNESCO Secretary to the Canadian Cultural Property Export Review Board, 1984-1999
Funding Culture in Paraguay
by Oscar Centurión Frontanilla Cultural Attaché, Embassy of Paraguay, Washington DC, USA
Support for Culture and the Hungarian Tax System
by Miklós Cseri Director, Hungarian Open Air Museum
Tax Incentives for Museums and Galleries in the U.K.
by Vicky Dyer Political adviser, National Art Collections Fund, United Kingdom
Bibliography