Perspex is a type of plastic, a decent glass store should be able to supply you with some. Hardware stores might too, but the bigger stores around Amsterdam (that are quite a bit like Home Depot) didn't carry it.
As far as the lappy cooler:
1. Added some thick rubber feet to increas the airflow between the lappy and the cooler.
2. Reversed the nuts'nbolts so that the big nuts are between the lappy and the cooler and no longer pushing into my flesh!
3. Added soft cloth feet to keep it more steady on flat surfaces and make it less slippery.
Number 4 will be the rounding of the corners and the edges (later today probably), beacause after just a few minutes I can feel the perspex cut into my thighs when the lappy+cooler is on my lap.
When it is finally really really finished, pics will be added once again.
As mentioned earlier; the next project is now in the ordering stage. As soon as all parts are in I will begin work on my lappy cooler Mark2. -> Peltier cooled air for the intake(s)!