Government Accountability Office Act of 2008 - Revises certain administrative requirements for the Government Accountability Office (GAO).
Requires the Comptroller General (not the President, as currently) to appoint the Deputy Comptroller General, who shall serve at the Comptroller General's pleasure.
Establishes an Office of the Inspector General in GAO.
Requires the Comptroller General's annual report to Congress to assess the overall degree of federal agency cooperation with GAO audits.
Requires any executive agency (or component) that prepares an audited financial statement (or related schedule) to reimburse GAO the cost of any GAO audit.
Amends the Ethics in Government Act of 1978 to revise the coverage of certain GAO officers and employees under its financial disclosure requirements.
Increases from 15 to 20 the number of experts and consultants whose services the Comptroller General may procure for renewable three-year terms at rates up to level IV of the Executive Schedule.
Makes funds appropriated to GAO for salaries and expenses also available for recruitment-related meals and entertainment.
Authorizes GAO to accept any money or property received as a gift, devise, bequest, grant, or otherwise to aid or facilitate its work.
Revises the highest basic pay rate for GAO personnel from GS-15 to Executive Level III.
Caps the Comptroller General's annuity at level II of the Executive Schedule instead of his or her basic pay rate.
Revises requirements for: (1) the pay rates for senior-level positions at GAO; (2) voluntary separation incentive payments; and (3) basic pay for retirement.