UPDATE: I really put my foot into it this time! It looks like the leopard hasn't changed its spots, and OP is still up to its sleazy old ways. I apologize for giving them any word of mouth. Thanks to everybody for setting me straight on this one. If anyone reading this wants T&T stuff please go to sites like Flying Buffalo and Tunnels & Trolls and not the crappy outfit I posted about below.
This may only be news to me, but it looks like Outlaw Press is back. As you may know, they got into quite a bit of trouble not to long ago when they were accused of plagiarizing artwork. It looks like they've put that behind them and are back in the swing of things. They have a new website and it's being regularly updated.
They are the main source for T&T material out there, even counting Flying Buffalo (no MSPE, though). Their main claim to fame is their re-prints of vintage T&T rules, like the 4th edition, Monsters! Monsters!, and the legendary 1st edition, the first non-D&D RPG ever published.
They've also taken the system in new directions with Superheroes Power Trip, a set of T&T superhero rules by Ken St. Andre himself, and Gamma-Trollworld, which is the T&T answer to Gamma World. In addition they publish a lot of solo and GM adventures for T&T.
I haven't bought anything from them myself, so I can't comment on their quality or service. One peculiarity is that several of their rules are only available as spiral-bound books. Is that an old-school thing? Anyway, if you like T&T you'll want to check them out. If nothing else, they offer a bunch of free adventures that you can download. What's not to like about that?