Go to this website to download: Windows: [You must be registered and logged in to see this link.]
Mac: [You must be registered and logged in to see this link.]
Here are the basic steps for how to get it:

• The untether is for iOS 5.0.1 on iPhone3GS, iPhone4, iPhone4-CDMA, iPad1, iPod touch 3G, iPod touch 4G
  
• If you have one of those devices and are not on 5.0.1 yet, update now! The SHSH window is still open for 5.0.1 If you unlock via ultrasn0w or gevey, make sure you only get to 5.0.1 via a custom IPSW! See the guides at places like [You must be registered and logged in to see this link.] if you don’t know how. Once you’re at 5.0.1, use the latest redsn0w 0.9.10 to both jailbreak and untether.
  
• If you’re already at 5.0.1 with a tethered jailbreak, you have two choices:
  either run redsn0w 0.9.10 over your current jailbreak (deselect
  “Install Cydia” if you do that), or install the Cydia package prepared
  by the chronic devteam. The patches are the same regardless of which you choose.
  
• Some of you are using a hybrid 5.0/5.0.1 configuration. If so, do
  not attempt to install this untether over that setup! You will most
  likely get into a reboot cycle. Do a sync and fresh restore to 5.0.1
  then install the jailbreak + untether.
  

Same steps to put into DFU mode.
For People who didn't read my other post. Here's the steps for DFU Mode.
DFU mode = Device Firmware Update mode

DFU mode is a mode where the iPod Touch/iPhone will be made to force a
restore of the firmware into whatever version firmware it is given.

Getting your iPod Touch/iPhone into DFU mode is somewhat tricky, and it
may require some patience/practice because timing is essential to get it
to DFU mode and not into recovery mode.

1. First, Open up iTunes, plug in your iPod Touch/iPhone to the CPU's
USB port. Turn on your CPU's speaker and make sure it is loud enough
that you can hear it.

2. Hold down the Home button (top left for iPod Touch and top right for the iPhone with the screen facing you) and the Power
button (located on the front bottom of your iPod Touch/iPhone)
simutaneously, until the screen goes black and the device turns off.
(past the red slider/slide to power off screen)

3. Now let go of the Power button, but continue to hold the Home button. Your iPod Touch/iPhone should have turned off and the screen should not be on.

4. After around ~10-20 seconds, you will hear a noise (beep/ding) from
your CPU as if it had just recognized a new hardware device, now iTunes
should recognize it in DFU mode.

5. After iTunes recognizes the iPod Touch/iPhone, let go of the Home button otherwise it will go into recovery mode and you will have to do the entire DFU process over again.

6. You will know when you have put your iPod Touch/iPhone correctly into
DFU mode when the display is blank and that you do not have anything on
your device.

***Untethered means it doesn't need a computer to boot up your iDevice.***

Credits goes to pod2g for discovering exploit and adding in the codes.

****For Unlock via Ultrasn0w****
Please Go to Extras -> Preserve Baseband Mode
Current Baseband for Unlock: The supported basebands for the iPhone 3G and 3GS are 04.26.08,
05.11.07, 05.12.01, 05.13.04, and 06.15.00. The baseband supported for
the iPhone4 is 01.59.00.

If You Guys Need help. Feel Free to PM Me.
Thank You for Reading!!! +1 If I Helped! Thanks