best way to get my feet wet in bash?

I'm a complete UNIX n00b, but want to learn very badly. What is the best way for me to get my feet wet? Obviously learning how to navigate around my machine and some basic commands would be good... I've found the Oreilly "tutorials" and have "terminal in OS X" but a version that was released when tcsh was the default shell...

But anyway, I have the resources available to me, I just don't know where to begin? What would you guys suggest is the best way to go about learning? Make a new user and mess around with it? How am I messing around? I don't want to just be running around being like "OMFG cd /Downloads" "ls -a" - I want to get more in depth than that. I want to use my brain. Challenge me. Help me become a power user!

Thanks guys

I would highly suggest running a virtual machine with Linux or some flavour of Unix/BSD and learning in those because, if executed improperly, some commands can really mess things up. At least this way, if something goes wrong, you just create a new VM or restore from a backup. In other words, don't test and learn the innards of Unix with your primary work machine.

In a VM, don't feel afraid to break anything. In fact, the best things you can learn are from botched installs. Now, I realize that Linux/BSD/other flavours of Unix aren't exactly the same but I would say that 95% of what you learn is transferable.

Nice to see another *nix nerd (I mean that in a nice way)!

I know you meant it in a nice way. And I'm not a *nix nerd yet... I'd love to be though. Is there any FREE vm software? I graduated college in December, and am still broke working part time in a liquor store... I already shelled out for a MacBook, I don't really have money to pay for VMWare

*edit* okay I found virtual box. I'll try to set that up. Would Darwin work if I installed that? I don't know, what OS would you recommend for sure? What do you think is the most easily transferable... probably something in free bsd? Is Darwin in freeBSD? I know it's basically the open source version of OS X

I use VBox myself so I can vouch for its quality. While not quite up to par with Parallels/Fusion, it is nonetheless a solid product.

The choice is up to you. It could easily be argued that Linux is easier to setup so it might be a good start. That said, Solaris and the BSDs are actually Unix (Linux is Unix-like) so it could be argued as well that these are more like OS X. The choice is up to you as these OSes share quite a bit of software. If you're new to *nix in general, Linux might be a good start or one of the more desktop friendly Unix OSes such as OpenSolaris or PC-BSD. While they may be geared to the average user (more or less), you can still tinker with them.

I couldn't get Darwin working in Vbox, but i'm downloading opensolaris right now... will let ya know if I get that done.

Darwin is tricky if not impossible to get working in VBox right now. The PureDarwin project has an ISO image but I believe I read somewhere that it will only work in Fusion. If you're interested, here is the download page in case it actually does work (or you figure out how to get it to work).