Do I need to waterproof the external walls of my house?
Here are a couple articles from AskTheBuilder.com.  

Exterior Foundation Wall Waterproofing

Foundation Waterproofing

This is one of those things that builders and homeowners usually cheap out on, which in my opinion is a BIG mistake.  Spending the extra money now can save you tons of money later, so do the research and do it right.

I've seen DELTA®-MS used before; but I cannot vouch for it as I have never used it my self, it seems like a good product though.

Here is an article from concretenetwork.com that seems to be very informative, and explains different methods of waterproofing concrete.

I'm not sure how much of this information applies to your particular situation, but it should give you a good idea of some of the products and methods used for waterproofing below grade concrete/brick.