Mariann Asanuma is reporting on her Modelbuilding Secrets Blog that we've had one confirmed purchase of Series 2 Collectible Minifigures at a Toys R Us in Texas.
I originally saw Tony Sava's announcement on the BrickLink forums. He has compiled a rough bar code cheat sheet which can be seen here. Expect more refined cheat sheets to surface soon.
Speaking from personal experience, I would find out which days are delivery days at your local TRU and call asking if the figures are in. I was only able to get some of the Series 1 figures due to a fortunate trip to the LEGO Store and lucking into the day Shop @ Home lifted the package cap. There has been no evidence so far that the US will be getting more Series 2 figures than we saw with Series 1, so be vigilant!
I would also recommend having a cheat sheet or bar code reader handy if you want to pick through for select figures. The success rate of the 'feel method' is rather low in my opinion. Recall that Brickset has their mobile app that can turn your Android phone into an impromptu bar code reading device.
One piece of new news...Mariann talked to Steve Witt from TLG and he claims that figures have been designed up to a fifth series!
Guides will be updated with relevant information once they become available.