UNIX command line: where can I learn???


je suis donc je pense
I have a few questions about the UNIX command line. If I learn the OS X version, will all the commands I learn work in other UNIX variants like Solaris??? Also where is the best online tutorial to become a UNIX command line geek :D (preferably under OS X)?? I find the www.macosx.org tutorial is not bad, is there anything more worthy of my time??

there are some subtle differences between Solaris, OSX, Linux etc as far as regular user level commands but it's not like they're
different languages. A few commands may have different options and things like that but if your comfortable in one, you'll be comfortable in the others.

Things change when you get to other things like trying to get stuff compiled or startup or other supervisor/root kinda things.

Really, any decent intro to Unix book would work.
For Mac OS X get a unix book that covers BSD unix commands. The more popular flavours these days are SVR4 (System 5 Release 4) unix (eg: solaris et al.) The commands usually have the same name across BSD and SVR4, but the options are often different:

eg: Mac OS X: ps -aux
Solaris: ps -ef

achieve the same thing. A good general Unix book I have is UNIX Unleashed (SAMS) which covers most areas of unix and sys admin. To really learn the commands it might be a good idea to get a book on shell programming.
Is MacOsX.org a good place to learn or should I invest my time somewhere else? Thanx for the links. I don't really feel like buying a UNIX book even though I know it would be a good investment. I will hav to buy one for scholl sooner or late.
I was wondering if anyone had a recommendation for a good Unix Shell scripting book. I want something that doesn't assume you're a programming genious from page one. A book that that starts with the basic and builds into the advanced and more complex would be great. I hate books that start with the complex and skip over the base knowledge stuff.

I currently have "Using CSH and TCSH" by Paul DuBois. I highly recommend it for beginners in the Unix command line world. Unfortuntely it doesn't get very advanced and does not cover shell scripting. Instead it covers maximizing use of the file system, command line, and user environment from the terminal. I think it also does a great job at starting easy and getting more complex for what it does cover.

So if you have any recommendations for a good book analogous to the one I mentioned above let me know. The book would ideally cover shell scripting for writing what would be called command procedures in the VMS world and advanced command line operations like compiliing, installing, mounting, etc..