What why and where?
 

Hey guys, im a long time Mac user but I want to have a Linux computer in my office for web based stuff and fixing hard drives.... I'm going to buy a used computer from eBay to install my Linux software as I believe that Linux is a lot faster than Mac or windows and doesnt need the latest hardware to compete.

In order to be at least as fast as a windows computer but no more than $100. What range of computer should I be looking at? What specs should I look for? And once I get it should I run Ubuntu or mint for web based things and hard drive repair? As you no doubt know, the Linux lingo is a bit difficult sometimes so please bear with me. I'm doing the best I can.

Weird question I know, but I'm sure you know what I mean.

As far as the hardware, check the Ubuntu or Mint sites for minimum hardware requirements which will be listed on their download pages. That way, you will know what is required from the hardware.

This computer has an AMD Sempron 2600, equivalent to a P4. It's slow for Firefox, but fine for Opera. It has 1GB of memory, which is a bit cramped for the Gnome or KDE desktops, but good enough for Xfce or Mate. A quick check on ebay shows that sort of thing at under $40.

I also see a HP with Intel Core 2 Duo, 4 GB RAM, 160 GB HD at $75. That would run anything.

I'd recommend Mint Mate or Antix MX: see the reviews on this site and via the Distrowatch pages.

Range> dual core

Ram> 2 gig

All other suggestions are covered pretty much.
That being said. My newly arrived 59 buck Atom N270 touchscreen 1 gig ram netbook (I bumped the ram to 2 gig after fedex delivered it) is the bees knees running AntiX 14 RV A5 patch testing.

I'd buy this one (hypothetically) today and put either Linux Lite or Handy Linux or MX-14 or Salix fluxbox on it (for example).

You probably have a few more decisions to take than you realised when you wrote this. The one that comes to mind is which GUI you will use.

If you get at least 2G of RAM, you could consider KDE or Gnome, but if you go much lower, it will probably crawl if you try to do much at once. That would then leave you the choice to make from things like XFCE, LXDE. Now, my advice would be to get a 'live DVD' or few with some candidates on them, plug them in, try them out and see which you like.

Primarily, if you like the GUI, you'll probably be ok with the Distro, almost irrespective of which you choose (well, I wouldn't advise, say, Gentoo as being the easiest place to start). Another way of going forward would be to choose one of the 'big, do everything' distros (Debian, openSUSE, for example) which would allow you to install several GUIs at the same time, and select when you log in. This would, of necessity, use more space on disk, so probably isn't a good route if your computer is short of disk space, but if you get a, eg, 160G disk, that probably wouldn't be an issue. (Still, using the Live CD/DVD, probably is less messing about before you know what you are doing, so is less likely to leave unnecessary rubbish on the hard disk in your experimentation.)