For a 3rd party Delphi ADO component check out
DiamondADO:

http://www.islamov.com/

For OLE-DB drivers for Interbase/Firebird check
this link out:

http://ibp.lcpi.lipetsk.ru/eng/links.html

Tell me if you have good or bad experiences with
both the OLE-DB drivers as well as Diamond ADO.