another good place for caps is
www.graffiti.org under the shop section the artcrimes store sells every type of cap you could possibly need along with top notch paint cuz painting with krylon doing mural or graffiti work sucks montana paints are the shit they sitck to any thing and even have glow in the dark paints they are like the house of kolors of the graffiti world they even remake old colors no one makes any more