Gosh you guys make me feel oooolllld!! I read the books when I was 10, pushing 13 years ago now. Man they are a hard slog! I'm from NZ, so like everyone else in the country I went completely ballastic about it when the film crews arrived. :-D I actually did four nights of extra work (I mean, so did practically everyone else in the country, but you can see my face in the final cut, so I'm happy). I think that the movies are fantastic movies, if you take them at face value. I think that in some ways, they DID massacre the source material, but then again, all movies do. But I'd also have to so, some of the scenes would have just been TOO BORING to watch in film. I mean, the Council of Elrond ALONE would have been 3 hours. And frankly, if they had structured Frodo being captured after Shelob the way the books had, there would have been a riot.
My only foray into cosplaying Tolkein (I don't count extra'ing) was when my friend and I ran a semi-costumed marathon of all extended editions as part of our Tolkien club. May I just point out, that this is a really good way to never want to see the films again? I sewed up a corset top in one evening from a pattern I already had, wore it over a poets shirt and a long skirt.
I think if I did a full scale cosplay, I'd probably do one of the Rohirrm, probably Eowyn. I'm kinda stuck on that style of costumes at the moment. The patterns you can by in NZ now have lots of imitations of LOTR costumes.