The basic truth is, you're going to come across fake and stolen merchandise in Islamabad. Depending on the area, or market, where you're shopping you may have a hard time finding anything that's legitimate or not stolen. The black market is not hidden in Pakistan and in many ways is a part of everyday life. Businesses will even give you receipts for black market merchandise, and treat it as if it's legitimate.
A good example is the DVD market in Pakistan, you will not find original legal copies of any movies or television shows anywhere. Yet there are several large stores that sell DVDs for very low prices (about $1 US per movie). They even openly label the pirated films depending on whether or not they are filmed in the theater versions or copies downloaded from an original source. They mark them as either "watchable" being filmed in a theater or "master" from the original DVD. Electronics and brand name fine jewelry fall into this same category, and while the price is great, the quality may not be so great.
Clothing is a little harder to tell, but it's a safe bet that if the price is too good to be true, it probably is. The good thing about clothing however is that there are many local clothing stores selling their own designs well worth checking out instead. Islamabad has some really amazing finds and local products, so while you might not find originals of some of the big brands of clothing, you will find some great local original products instead.
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