just to add what Frank said: the white plastic control cover has 6 tiny clips; two either side of the sliding switches and two in the middle. I found that gently levering the cover up by inserting the tip of an Xacto blade through the holes the sliders ride in avoids damaging the clips. Be careful not to turn the iPod on when you do this or scratch the green paint next to the on/off slider.
Tri-wings are quite sensitive to which size driver to use. I found Pro'sKit brand size 0 seems to fit these very well.
The magnetic latches are about 2-3 cm from the left and right edges right at the top edge of the case. I just ran a rare-earth magnet over the from of the bezel in this area. You can hear it click when it disengages. RadioShack has these kind of magnets for $3, the call them "super magnets".
I really like iFixit, I think they sell good quality parts and I've used their guides for several repairs:
iPod Nano 5th Gen battery -very difficult, you will need a new back
iPhone 1st Gen battery -not difficult but case gets a little cosmetically damaged
iPhone 4 back -easy
iPhone 4 display/digitizer - medium but long
iPod Touch 2nd Gen headphone jack and digitizer - very difficult
I think my soldering skills are at least average and I'm fairly good at making/fixing things.
That being said, I have to call this video above out. It is in no way representative of how hard it is to get the screen out of an iPod Touch 2nd gen. Would I go as far as saying it's fake? Almost. Definitely heavily edited. I seriously doubt it's possible to remove that screen without any damage. It seems very suspicious this video doesn't show any moment where the clips are actually being disengaged. That's the moment you are going to be levering the hardest.
My advice, always buy a new screen if you open this iPod.
The inverter connector comes off vertically from the motherboard.
There are four plastic clips above the CD slot that may come off or stay attached to the uppercase. On reassembly remove them from the upper case and locate the clips into the slots in the frame inside the lower case before lowering the upper case down into position.