Im new too, I also was a Honda dude. Had a coupe 95' Honda civic, put a bolt on turbo on it, had my fun with it passed it over to my brother. Got an IS300 now(love it, sucks in snow!).. dont know If I want to turbo this though..
Now please please please... don't rice up your Lexus. The Honda guys have a bad reputation for doing silly appearance mods to their Lexus IS's. They also have a bad reputation for crashing IS300's in the rain... and then blaming the crash on RWD.
Treat your car right! Welcome to the site... if you search you'll find plenty of info on mods.
LMAO!! I see those all the time! They think there cars can run the quarter mile in 5 seconds.. oh and the higher their spoiler the more horses you get. I had my civic pretty much clean. Civic was red, black front lip(NO! bodykit, spoiler or neon lights), black Halo headlights, 17 in black rims with chrome lip, and a turbo.. none of that ricer crap..
I honestly can't think of many interior differences. There's an Altezza instrument panel that has a digital speedometer. I always thought that was cool. All cars here 2002+ had armrests in them. There are TRD Altezza steering wheels that are a combination of red/black, blue/black or even carbon fiber and black.
Other than that I don't think there's any real things there on the stock interior that didn't come here. You'd probably be looking at OEM factory accessories for "JDM" stuff.
I have seen the instrument cluster where the speedometer was the tach and the tach was the speedometer. I believe it was a special limited production from TRD, but I am unsure. Maybe you could look into that.
And Crester sumed it up perfectly, don't get stupid wings and other Honda accessories. It looks dumb.