If you uninstalled the City of Heroes client after the official servers shut down, shame on you! But, we got you covered. And if you lost it because you uninstalled the NCsoft Launcher and it deleted your game folders including all screenshots, costumes and story arc... I'm really, really sad that it happened to you. We got you covered as well. There's two options: BitTorrent, or patchers.
If you don't have a torrent client, I personally like Tixati.
Please seed! This is not a big release full of people downloading it, it's just for the City of Heroes community and those who refuse to let the game go away.
If the torrent is no good for you, there are two tools that will download all the game files directly and keep Titan Icon up to date: Tequila and Island Rum.
Island Rum is the patcher for Mac. The link leads to a post in the Titan Forums with download instructions; contact Manga on that thread if you need help or have any issues.