I'm behind a router that can't be configured, and so I can't set up port forwarding. Anyway, I'm trying to test and play my map, and I don't know where to go to find someone that will help me host it. I have a friend, but he's usually busy doing other stuff. Any suggestions?

buy a new router =)

It's not my router. I live in an apartment where the Internet connection is provided to me. The ports for Battle.net are open, but I share an external IP address with many other people.

The first post seems to suggest that you can't forward the necessary ports, the 2nd says you already have.
In case port forwarding is your problem you can change the bnet port in your registry to 80. This is the port used for browsing the internet, thus it's safe to assume its open.

Just so you know, most ISPs block port 80 inbound because they don't want people hosting websites from their house.

To get people to host for you, join a clan, such as RCDF ;D

Is there a better one?

Sorry, I forgot to reply. I found out that a nearby computer lab will let me host games. I just take Starcraft on a USB drive and plug it in. I used this one loader program to put it in windowed mode, but I'm not even sure if it was necessary.

Thank you for the help.