Buying a cell phone

Hi, I am moving to Tokyo very soon and I'll be here for about 2 years and so I need a cell phone. My Japanese is right now at a basic level, so I'm nervous about being able to communicate what type of cell phone/plan I need. I have a ton of questions, so be prepared hahaha.

So, my first question is, can someone tell me how to say certain phrases in Japanese that are needed in buying a cell phone..I just don't want to look THAT dumb hahaha!

Also, I'm from the u.s. and I was wondering whenever I get a cell phone, can I send sms messages to people living back in the states? or do I need a certain plan to be able to do that.

Another question, I have heard that some phone carriers will accept the certificate(I think it was??) that you can get after you apply for your alien registration card, but I forgot what companies accepted that. So, does anyone know??

Last question, how do you usually pay your bill?

Thank you for whoever answers all of these questions ahaha

most softbank stores have english staff so no worry. if you feel like wasting time, then you can go to roppongi softbank where all the not well ajusted people seem to go to, but i advise against that as waiting times are bad.

i went to softbank omotesando and they didnt have the phone i wanted.

i ended up having to speak japanese and go to a store that sold softbank phones. it wasnt that hard to be honest.

hope that helps

Basic info
http://www.japan-guide.com/e/e2223.html