Ok before you tell me to search the forums before I post

let me tell you I've done some searching and also i've done alot of searching on google... My question is somewhat scattered and has several parts... anyway
I've got a great background with Windows, DOS, and hardware tho no official certs at the moment... just work experience and obsessive geek learning

I do some freelance computer consulting work for people with Windows. I'm just getting into Linux and I have a LOT of questions, but the ones that come to mind are this...
In Windows, I would often find it good practice to uninstall an old version of something before installing the new version. I know its not always necessary, (sometimes it has been tho) but it does seem to clean up a lot of messes. Just out of curiousity, is that a good idea in Linux?
We have the Add/Remove programs window in Control Panel in Windows. Where would I go if for example I wanted to uninstall WINE... I didn't do it through the software repositories, because they didn't seem to have the exact version of WINE I wanted, so I went to the winehq site itself.
Also I see that Fedora uses the .RPM package method for installing things. Looking around the internet at the things available for install on Linux there are usually tar.gz packages... Now I'm guessing that RPM is Fedora's equivalant to Microsoft's MSI installer, and tar.gz is equivalant to .zip or .rar in Windows... Well there seems to be a LOT of things available in tar.gz packages, and I'd like to know how to install them.
One such program for example is the great MetaSploit program which is available at
http://www.metasploit.com/
http://www.metasploit.com/tools/fram...napshot.tar.gz to be exact... I've been using metasploit in Windows, but I want to examine and begin to use it inside of Linux as well, increasing my knowledge and learning about computer security. Thing is I wouldn't know the first thing about installing it under Fedora. That or a dozen other very cool programs and utilities you can only find in Linux.
Well, I understand there's alot of things compatible with Unix like systems in general and my guess is that to get them to run on my installation of Fedora I would have to do some poking around in the configuration files, adjusting certain filepaths, etc. pointing certain things to certain places so the files they're dependant on can be found, etc, but I don't know for sure... Well I'd sure like a response to my rambling thoughts and questions, I hope I have been coherent through all of this. I understand its one helluva lot easier to
just use the repositories, but truthfully speaking, they won't always have the things I need.
Anyway, thanks for your time and effort to read all of this, and I certainly hope for some good responses. If there is a website I could go to(besides this one, lol), which would help with the transition from my Windows knowledge to Linux, I would certainly appreciate it. Thanks a million.