Does the law of Minhag Hamakom still exist in our days? ie. does one in yerushalayim still HAVE to wear stockings in following the minhag etc? I heard that we don’t follow minhag hamakom anymore because there are so many different types of people in one area that its hard to apply it.

The concept of Minhag Hamakom still exists today even though in respect to certain laws the greater mobility of today does change its application.For example: someone may be davening Shacharit in a shul that uses the Askenazic liturgy, Mincha in another shul where the davening is Spharadi, and Maariv in yet a third shul where another Nusach is accepted. As a result, the individual- when praying quietly in his place and not acting as the Hazzan(cantor), would continue using the liturgy he inherited from his father and not change it, as he would have done in past generations, to the liturgy of that community in which he now resides(Shu"t Iggrot Moshe). The community's traditions are less binding on him because the definition of community is today more fluid. That said, the laws of modesty include the obligation on a woman not to expose parts of the body that in a given society are normally covered (this in addition to the obligation to cover certain parts of the body regardless of the general norm). Therefore, one visiting a community or living in a community with definite norms that are more severe than elsewhere should dress according to the accepted norm. It would however, be incorrect to see all of Jerusalem as a single "makom" with a unified minhag in:re to the specific question that you raised.