uglyb0b: I think I must have misinterpreted what you meant then. What I posted is what you need to do to get back to 100% stock GB.
On some roms, when you flash back to stock with Odin, you will get a whole load of text on the recovery screen saying things about not being able to mount certain paths and it will not give you any "install from sd/wipe data/wipe cache etc" commands.
If this is what happened to you, then boot into download mode, flash stock rom. Then unplug and pull the battery out, put it back in and boot into download mode. Flash the file in the dropbox link and the phone will automatically reboot and you'll be running 100% stock with stock recovery.
If this isn't any help to you I must have misunderstood the problem you were having.
uglyb0b: The best thing to do at this stage is to flash back to stock and start again. Download the stock 2.3 rom from sammobile, flash in Odin, wait for it to reboot and then flash the file I linked to earlier in the thread.
I have encountered the lost IMEI situation before (can't remember if it was when I was doing some modding or if it was a friend) either way flashing back to stock and starting again fixed it.
Let me know how you get on.
uglyb0b: If you're using Odin you would unzip the file you downloaded which will get you a .tar.md5 file. You would flash this file in Odin (you won't need a pit file). Heimdall works a bit differently but you should be able to use that instead provided you use the right files (I'm much more experienced with Odin than Heimdall though). Do you have a windows pc you can use Odin with?
uglyb0b: Glad to hear you got it sorted. If it's working as you need it to now then that's fine, but I wouldn't go swearing off modding completely (that's half the fun of android) especially now as you have a confirmed working way back to stock if it messes up.
If you're interested, when I was using an I9000 I was running cyanogenmod (very good stable rom with better performance than stock). The cm team are working on 4.4 nightlies for it at the moment so will likely get a stable release at some point. The latest stable build is cm 10.2.1 which is based on 4.3.
Either way if it's working fine on stock then you can leave it as it is, just letting you know of a few options if you get bored.
uglyb0b: You can fix almost any software related issue with Samsung phones if you can get into download mode. You would do this by holding volume down, home and power keys (slightly different on some US variants without home keys). Download mode is all you need to flash firmware with Odin.
If the device is boot looping, that may indicate corrupt data in the system partition. If you can get into download mode normally flashing stock firmware will fix this, however if it is the bootloader that is damaged/corrupted it gets a bit more complicated.
Recovery mode is normally accessible through volume up, home and power, however this varies between models.
In regards to fixing bricked phones, this would depend entirely on what caused the phone to become bricked. As I mentioned earlier, bootloader problems can be messy. Physical damage can cause issues as well, I had a Galaxy S II with a corrupted IMEI. I worked with various nvdata rebuilding tools before finding out the problem was a faulty RF IC, so nothing software can fix. My point is - make sure you are aware of the extent of the damage of any device before buying it with the intent to restore it.