Take a look at these sites
hOurworld — official website of hOurworld
TimeBanks USA — official website of TimeBanks USA, Washington DC
Dane County TimeBank — official website of the Dane County TimeBank of Wisconsin
Portland Hour Exchange – official website of the Portland Hour Exchange of Maine
New Economics Foundation -official website of the New Economics Foundation of the United Kingdom
TimeBanks United Kingdom – official website of the TimeBanks of the United Kingdom