Oracle Database Discussions

Hi, we have an Oracle RAC 10gR2 EE on SLES 10.

I have tables with 300.000.000 of records. These tables need some indexes because it access is very very slow. I check that it need one index for each foreign key. I have a lot of tables, and I'm looking for some tools or sql sentences or similar that says me, the index of the tables for each foreign key. For example, I need to know what many index left to me to complete the processes and which it.

Table A
ID (PK)
B1_ID
B2_ID
C_ID
D_ID
...
...

(B1_ID,B2_ID) FK TO TABLE_B
(C_ID) FK TO TABLE C
(D_ID) FK TO TABLE_D


I have create the index in the table A, for table B, but I have not the index for table C and table D.

I have a lot of tables, with many foreign keys.
How can I know what indexes I need create?

Thanks you very much.