Q: How can I replace a battery in a 5th generation 30GB with video?

You can still send it off to a third party repair center and have them swap the battery out for you. Just do a Google search for "iPod Battery replacement" and you should get a number of results to work with.  Here is one such option.

http://www.ipodbatterydepot.com/

Otherwise there are also numerous places on the web where you can buy a new battery from.  You can then swap it out using the appropriate guide over at http://www.ifixit.com/.

B-rock

No problem.  Glad to have helped.

B-rock