OK, I am stupid but I need specific help on what kind of hobby phone to use. Keep in mind, I will be using this ONCE for maybe 2-3 calls as I am traveling to see a well-reviewed provider in Vegas. It will then be destroyed.
So I need someone to tell me EXACTLY what brand and if possible model of phone to buy at say, Walmart, knowing that I would like it to be used in two different states, and is cheap since I will only be using it for like a week. Texting would be nice but not a must.  Thank you!

pay with cash, use fake name and address.  Maybe a Tracfone, that's the only one I know of offhand.  I've never used one, being unattached.

I think tracfone will get you the cheapest phone and somewhat cheap minutes. If you have the time, you can often get free or $10 phones via their website. Their minutes aren't the cheapest, but for this instance the phone subsidy may be more of a benefit.

More selection & sometimes cheaper than WM.   WM doesn't have many choices.

The phone number resides on the SIM card so if you destroy it (little tiny memory card inside the phone) then the number is gone too.
If you get an unlocked phone then you can buy a new SIM card for your next trip, and install it into the body of your phone.

Ok thanks all for the advice but I need more info. So let's say I buy a trackphone--then I need to buy a card right? How does one register a Trackphone? And will said Trackphone work throughout the US? (See, I told u I was clueless.)

TF normally comes with like 10 minutes when you buy the phone. You can also buy a refill card at the same time, sometime in the future or just buy minutes online (tracfone.com) without a physical card. To be truly anonymous though requires a card, paid with cash.

THANK YOU--I will follow your advice. One question though....I will follow your advice and pay with cash, but if I used a debit card, how could that ever be traced to me--I mean how would anyone know what a certain charge on my debit card was for--i.e. I bought something at a convenience store--how would they know it was for $10 worth of slurpees?

but buys time on other carriers  
KI just found this info:  http://thejmart.com/markets.htm  
I'd buy the phone on arrival, if possible.  Do the date set up over email prior, if you wanted to.  I don't know about Vegas...  maybe ask on the regional board for that arwa...  but besides WM, druug &  convience stores carry them.   I don't know if you'd go over the 10 minutes that comes on a new TF.    
If you really don't want to carry it home, by all means drop it in the trash or leave it behind somewhere.  20$ phone & 20$ service card.   If you really can't risk keeping it, minimal loss.

I suppose that's true. My bank statement shows debit transactions as the location only.