I took networking courses at a community college. The professor was fantastic, a former IBM employee who'd been doing network stuff at AT&T for 20 years. He wasn't a professor, but this guy knew his stuff. It was the perfect way to get some "hands-on" experience with routing and switching.

Community colleges don't do everything well, but when it comes to building hard skills, it's hard to think of a better bang for your buck. (Particularly if you live in NY like me, it's free!)