I'm experienced with computer programming, proficient in about 6 or 7 languages. However, I don't understand how to make Ipod Touch Apps. Like toolchain and everything. If someone could just tell me how to make a Hello World app, I'm not sure what language to use.

This compiles easier than the HelloWorld app. There are no errors in it and virtually no UI.
http://www.ipodtouchfans.com/forums/showthread.php?t=13483

These are the best instructions on compiling the toolchain on the web. The biggest mistake that people make is not making sure ALL symlinks are working.
http://code.google.com/p/iphone-dev/wiki/Building

Objective-C is a superset of C, just like C++. If you have a handle on C++, then you should be able to pick up Obkective-C fairly well. Also, try this site for code samples.
http://www.idevdocs.com