I found it for you:
http://support.sprint.com/global/pdf/user_guides/htc/evo/htc_evo_ug.pdf
Page 169. No sticker, but in the manual.
From my personal anecdotal experience with my i4 all the websites claiming doom and gloom were the ones spinning to me. Ars did a pretty good test showing that the new phone can lose ~20db of signal when held a certain way. That's enough to lose 1-2 bars and if that's all you have then it's definitely a problem. The most I can get to happen is 1 bar and it generally then bounces back up.
Apple brought the issue to light that has been a problem since phones started moving their antennas internal to the phone. A friend with a BB just IMed me laughing that he can do the same thing on his phone because of the weak signal he has in his office building.
I think Apple did all they could here. There is no way they have time to engineer, test, and possibly get FCC approval for some new phone in such a short amount of time. If the bumper isn't enough for people then return it. My i4 works fine with my usage and is much better reception wise than my 3GS was. Not that the 3GS was a stellar performer, but in places where I would drop calls on the 3GS (I live near the mountains) the i4 hasn't dropped yet.