1)   Devrace FIBPlus for Borland InterBase and Firebird 6.0
The simplest and most flexible suite of direct access components to InterBase and Firebird. Supports SQLDialect 3 of InterBase 6.x, array and blob fields, implements local filtering and local sorting in dataset, supports standard data-aware controls.
interbase, firebird, delphi, bcb, sources, db, engine, connectivity, ibo, ibobjects,

 2)   Open QueryBuilder 4.01
Freeware with full source code! The Open QBuilder (OQBuilder) is a simple "visual query builder". You can use OQBuilder in your Delphi and C++Builder applications to make easier SQL-code generation. Supports BDE, ADO, IBO, IBX, DBX, FIBPlus, etc.
BDE, ADO, IBO, IBX, DBX, FIBPlus, SQL, visual, query, database,