Ok there are some other guides here on the forums for this but they all require you to download the Android SDK. That can be very time consuming and confusing if you run into issues. I have been looking at a way to have the capability to push and pull files using my laptop but i really didnt want to go through downloading and setting up the whole SDK just to use adb.
If anyone has followed any of my threads, you know I am all about trying to get things done in the easiest way possable to help the people that are new to Android. This method has worked for me but there is no guarentee that it will work for you and I am no way responsable for anything that happens to anything

unless it works great for you. Then I will take all credit

j/k. With that being said:
The first method is for Windows based OS. I have tested it on XP but I would imagine it will work on any Windows OS. If I am informed of something different I will update it here. The Mac version is in post #2 and takes less than 1 minute to do. Much thanks to kwbdc and stlouie65 for the help on this.
Instructions for setting up Adb/Fastboot (windows)
1. On your phone go to Settings/Applications/Development and make sure USB debugging is ON and plug it in via the usb..
2. Install drivers on your PC. This is done on the MT4G/HTC devices by going onto your sd card and clicking on the
HtcDrivers.exe file while viewing the files on your PC. It should automaticly install them to your PC. If you are using another phone or have trouble installing the ones from your sd card you can try pda.net or HTC Sync for the drivers. Here are links for pda.net
32-bit Windows 7/Vista/XP and for
64-bit Windows 7/Vista. Install the program by hitting "Run" and follow the instructions. You can remove it at a later time.
3. Download the file at the bottom of these instructions to your desktop and extract the contents. There is 1 folder and a install note (these instructions) that should extract. You can use a program called 7-ZIP (google it, its free and a great tool).
4. Open your "Start" menu and click on "My Computer". Then choose "Local Disk C:".(You can now click and drag the adb folder you extracted to the C: drive.
5.Open a command prompt and type
cd\adb and hit enter. You should now see something that looks like this C:\adb>
6.Type
adb devices then hit enter in the command prompt and it should list your device.
7. You can also type
fastboot devices then hit enter in the command prompt an it should list your device. (you must be in the bootloader for fastboot to recognize your device)( adb command=
adb reboot bootloader )
You should now be ready to send commands to your phone via ADB or Fastboot. You will need to repeat steps 5-6 anytime you want to use ADB/Fastboot. To send a file using Adb or fastboot make sure to put the file in your "adb" folder before giving the command to send it to your device.