'04 RSX - oxygen sensor?

First off, I did try searching, but it seems most of the O2 sensor questions are pertaining to older models.

So, my check engine light is coming on occasionally. It's definitely not the gas cap, because I make sure and get it tightened down every time. I had a dude at AutoZone test it for me and he said his report looked like it may need the O2 sensor replaced, but he also didn't sound 100% sure, either.
Is this pretty pricey and/or a pain to replace myself (I do have plenty of experience working on cars)?

Thanks in advance!

Reviving an old thread as I just got the P0134 Error Code regarding possible O2 sensor problem....

Did original poster replace sensor himself or take it to shop?

Anyone have info on how to replace this sensor?

Do you have to jack up car to do it?

Need any special tools or just socket wrench, etc?

Thanks for any and all input...

Mark