Concatenating multiple lines based on a condition

[webecho]

I have a spreadsheet exported from MYOB ...
The format makes it useless for my purposes without a lot of manual deleting and copy/paste, so I'm trying to clean it up automatically.

4 Columns:
[TABLE="width: 500"]
<tbody>[TR]
[TD]A[/TD]
[TD]B[/TD]
[TD]C[/TD]
[TD]D[/TD]
[TD][/TD]
[TD]Row Number[/TD]
[/TR]
[TR]
[TD]Product ID[/TD]
[TD]Product Name[/TD]
[TD]Date[/TD]
[TD]Quantity[/TD]
[TD][/TD]
[TD]1[/TD]
[/TR]
[TR]
[TD]Prod-1-Code[/TD]
[TD]Prod-1-Name[/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD]2[/TD]
[/TR]
[TR]
[TD]Useless Info[/TD]
[TD]Useless Info[/TD]
[TD]Useless Info[/TD]
[TD]1[/TD]
[TD][/TD]
[TD]3[/TD]
[/TR]
[TR]
[TD]Useless Info[/TD]
[TD]Useless Info[/TD]
[TD]Useless Info[/TD]
[TD]1[/TD]
[TD][/TD]
[TD]4[/TD]
[/TR]
[TR]
[TD][/TD]
[TD][/TD]
[TD]Prod-1-Name[/TD]
[TD]2[/TD]
[TD][/TD]
[TD]5[/TD]
[/TR]
</tbody>[/TABLE]


Above is a simplified version of what I have.

What I'd like to do is combine the good info on one row (preferably in 3 cells)

Prod-1-Code Prod-1-Name 2 (total quantity)

The problem is that each Product has a different number of rows of "Useless Info"


So what I'm trying to do is say:

If the text in columns B and C matches
THEN
get A, B and D and put it somewhere.


I've tried a few ways and failed and I've not had much luck Googling as it's a bit difficult to describe what I want to do.


I really hope this makes sense to someone


Thanks in advance


webecho