Yeap!!! found some sources for N900 screws! i know it's probably an issue with all DIY users like me who over-torqued a screw and messed it up, not to mention they were rare as diamonds on the net, here you go:

http://www.klc.fi/fin/tuotteet/Nokia-Varaosat-N900
http://www.thenokiaparts.com/eng/tuo...00-spare-parts

both are KLC Finland, some electronic shop in Finland, soooooo here you goooooooo! just ordered two from the first link, hopefully each one of these links is connected to a different warehouse, since the first one's stock is different than the other, fingers crossed, enjoy your full-in-parts n900.