Port Forwarding

http://portforward.com/english/routers/port_forwarding/Trendnet/TEW-432BRP/Apache.htm

The link above, along with specific information on logging into my router, gave me what I needed.

I've now verified

1. That I can use port 80 to see the website on my internal network from another computer, and
2.  That port 80 is seen as open from the external network.  (Nice tool for that at http://www.yougetsignal.com/tools/open-ports/ .  I saw that it was closed, and then changed my router settings to match the target server's IP address, and watched as port 80 was opened.

Unfortunately, apparently you can't connect to your own external IP through most routers.  (http://forum.teamspeak.com/showthread.php/88287-cant-connect-to-my-server-using-own-external-IP  See post 5.)

IP settings in Ubuntu

Two nice articles from sudojuice, one to use the default Ubuntu UI and one to use the terminal (hint: you have to disable the UI first!!) to configure IP settings in Ubuntu.

A useful find there is nm-tool, which is alike a superior ifconfig.

Here they are:
http://www.sudo-juice.com/how-to-a-set-static-ip-in-ubuntu/
http://www.sudo-juice.com/how-to-set-a-static-ip-in-ubuntu-the-proper-way/

Trendnet router reset: This makes me feel safer

http://portforward.com/networking/forgot-router-password.htm

Basically, if you ever were to lose the username and password associated with your router, you can put it back to factory settings using the reset pinhole.  On my Trendnet that pinhole is on the front right below the power jack.

For most TrendNet routers, the reset leads to
username=admin
password=admin

See the portforward link up top for more details if this doesn't work.