Before I put down money for hosting, I want to experiment with the codebase a while using self hosting. My question is how can I let people connect to it from outside?

I can connect to it just fine from my own system, and from other PCs in the network. However, when I try having someone outside the network connect, it fails. As I understand it, this has something to do with the IP address used within the network being different than the one used without.

Is there any way I can let people connect from outside the network?

Not sure the budget you're looking for, but I use Slicehost which gives you a virtual private server for a little over $20 a month. You can do whatever you want there.

About self-hosting, you can do it, but you'll have to configure your broadband router for the settings outside (depends on router). Basically you're looking to forward the port on the router, let's say 4000, to whichever machine on your LAN you're hosting the game on. For example,

Router (4000) to 192.168.1.20 (4000)

Its quite easy once you get the hang of the control panel on your router. The only router I've had problems with (and I'm a network guy) is the Verizon FIOS piece of junk. The labels seem to be backwards.

Zeno has a free site you can use for hosting. There are other free hosts out there as well.

As for your error it's probably a firewall issue, that or need to check ipconfig in prompt.

Alright thanks. I'll probably have to look for hosting, since I don't have control over the LAN at my school.

School, eh? Yeah, you probably have zero access to an external IP to properly forward ports to yourself. Sorry, that's a deal breaker :(. I self host with little more than an old desktop running Debian and a Linksys router with port forwarding.

So, you pay $20 a month to have a shell account? I read the info on the link and see that you have full root access, so I'm assuming that it's a pretty sweet setup. Whats the speed / compile time like? I just use my windows box with Cygwin to build remotely, but when it comes to hosting i'm using Third Hosting. Its cheap, but limited.

You dont need any of that, just sign up at no-ip.com and make a FREE dns host using their servers.. for example I used to have my own linux server and used no-ip.com. All you do is give them a site name like mine was reign-sytes.net or .com and itll send whatever they are doing right to my comp. Its just a website redirection so people on the outside can connect to you. If you have a router, make sure you open the port to the muds port number so they can connect to the game.