Here are some direct links to help with these special topics:
Donations
http://www.nonprofitexpert.com/donations.htm
Pledges
http://www.compasspoint.org/askgenie/details.php?id=61
Tax Deductibility
http://www.allianceonline.org/FAQ/financial_management/what_is_tax_deduc...
Depreciation
http://www.allianceonline.org/FAQ/financial_management/what_is_depreciat...
Cash Reserve
http://www.compasspoint.org/askgenie/details.php?id=65