International Financial Statistics has a new, user-friendly interface.
This is where you go to find data on interest rates, financial reserves, money, deposits, GDP, prices, employment, production numbers and trade (and more).
Data is available for most countries of the world.
BTW, I like the different kinds of interest rates available: money market, discount, lending, desposit, and short or long government bonds (for most countries).
IMO, the best search method:
Go to Query Builder
Select Concept (tip: Interest Rates Hidden Under Financial Indicators)
Change the Time Period to Include Multiple Years (if needed)
FYI, sometimes historical data for certain concepts and countries is not available.