Well, it's apparently lacking of good transitions, since the original poster said as much in his post.
I would recommend that if you have iMovie HD already and there's a transition you're just dying for, export the clip(s) you want to add the transition to as DV files, load it into iMovie HD, apply the transition, export the new clip back out and then import into imovie 09. It might be a long process, but probably worth it.