Hip hop style

HIP HOP

The classic hip-hop style (since the early-mid 90s) has been baggy jeans, matching t-shirt and sneakers and hat. There's a variety in there regionally and time-period-wise (ie: throwback jerseys five years ago, grittier work and outdoor clothes like timberland boots 15 years ago, etc), but the general aesthetic is built around that baggy-jeans look. 

Hip-hop culture has over the past five-ten years slowly developed another parallel style. Think of how Pharrell dresses versus how say DMX dressed. Or even Jay-Z. The newer style is more fashion-conscious (that is, fashion-industry conscious) and informed by skater styles. There's plenty of crossover (sneaker obsession, for example), but the central conflict could be boiled down to baggy jeans vs. tight jeans. Kanye West, Pharrell, Lupe Fiasco, Drake, etc are all much more in the tight jeans camp. Not tight like punk rock tight (though "punk rock" is an urban fashion trend in the Bay Area, not meaning exactly the same as it would to the Ramones)... but tighter than super baggy.

Matching outfits

People definitely buy their matching outfits as a set. Lots of t-shirts and fitted baseball caps are made specifically to match the color scheme of a certain sneaker (say red-black-white for classic Jordans). It's unusual for shoes, shirt and cap to come as a set, but not unheard of.