I just searched 'star trek bloopers' in the search box at the top of the page, you get the old TNG/DS9/VOY reel that everyone's seen with John de Lancie fluffing his line 5 times, scroll down and you get a few other options including the ones I posted above. There aren't a great many bloopers for Star Trek compared to some shows, I think the producers, especially of the later incarnations, were of the 'bloopers spoil the shows suspension of disbelief' school of thought (As is Joss Whedon, entirely by the way, which is why Buffy/Angel bloopers are also very hard to come by)