PublicTenders.net has an archive of tenders for the whole of the EU, going right back to 1 February 2008. That's over 1.5 million documents in total – and a fantastic research resource.
TO-Nuku'alofa: EDF — rehabilitation of the health sector in Niuatoputapu (Extra information)
TO-Nuku'alofa: Supply and installation of photovoltaic panels (EIB) (Extra information)
TO-Nuku'alofa: sustainable urban and environmental management capacity building and environmental protection TG/001/07 EDF9 (Extra information)18 December 2008 | OJEU | TONGA (TO)