I believe I purchased mine on that site, it did take some time to get to me but I'd say it's well worth the wait. I didn't see them on ebay/amazon or anything like that which I did search for them. Order a couple of things at the same time so you don't have to sit and wait for one item, I suppose... would ease up the pain a bit, heh.
I agree with Steve though, lowering + bigger/aggressive wheels will set the car off massively since you're focusing on looks first.
As for the rear spoiler, stillen has one which is a bit lower key and lesser weighing version of the SR/SE-R/Spec V variant which you could always purchase the OEM aftermarket looking one on ebay. https://www.stillen.com/exterior/body-s ... l?___SID=U
Stillen also has other exterior mods like the front lip for your current bumper and/if you decide to swap it out for the SR/SE-R/Spec V bumper you can put that lip too.
Basehttps://www.stillen.com/exterior/body-s ... entra.html
SR/SE-R/Spec Vhttps://www.stillen.com/exterior/body-s ... entra.html
Rear bumper liphttps://www.stillen.com/exterior/body-s ... l?___SID=U
Roof Winghttps://www.stillen.com/exterior/body-s ... l?___SID=U
(I bought my roof wing from ebay.)