Do you have the same iTunes account on both devices? Also, do you iOS 5 on your iPod Touch?
If so, you can go on your iPod Touch and into the App Store. In the UPDATES section, you'll see "Purchased". Tapping this will bring up every single app you've ever downloaded on your account. You can scroll through - sadly there's no way to sort them to make it easier and you can't permanently delete any of them from the list - and select to download the ones you want.
The apps on your iPhone won't move to the iPod Touch, but you can download them onto the iPod Touch.
You can transfer apps from your iPhone to your iPod touch via iTunes. Run iTunes on your computer and connect your iPhone then transfer the apps. Then disconnect the iPhone and connect your iPod touch to transfer the apps to the iPod touch.