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.
SwimOK, 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.
Swim
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.
Conversely, a cheap phone from T-Mobile and their very cheap plans would be worth looking into.
If you have the gear (a USB headset, namely), you can get a free phone number through Google Voice. Works great, so far as you have reliable broadband/wifi. That's a one time $30 purchase (for the headset), then you can have as many GV numbers as you want.
More selection & sometimes cheaper than WM. WM doesn't have many choices.
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.
There are countless coupon codes online that will allow you to double minutes.
I don't think TF uses SIM cards.
TF has spotty coverage, but if you're in a major city you'll be fine.
You will almost certainly get someone's old number, so be prepared to handle that.
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?
There are countless coupon codes online that will allow you to double minutes.
I don't think TF uses SIM cards.
TF has spotty coverage, but if you're in a major city you'll be fine.
You will almost certainly get someone's old number, so be prepared to handle that.
I suppose that's true. My bank statement shows debit transactions as the location only.
I guess it's how paranoid you are. Are you married? Is your wife going to see that you went to CVS on Oct 24th and spent $10 there? Is she going to ask why? Is she going to go to CVS with a photo of you and ask the cashier if they remember you and what you bought?
Is the alimony lawyer going to establish that you pre-planned adultery by finding out you bought a burner phone via your checking account?
I'm a hobby virgin, but the established johns here will surely say Cash Is King.
The phone number resides on the SIM card so if you destroy it (little tiny memory card inside the phone) then the number is gone too.
If you get an unlocked phone then you can buy a new SIM card for your next trip, and install it into the body of your phone.
but buys time on other carriers
KI just found this info: http://thejmart.com/markets.htm
I'd buy the phone on arrival, if possible. Do the date set up over email prior, if you wanted to. I don't know about Vegas... maybe ask on the regional board for that arwa... but besides WM, druug & convience stores carry them. I don't know if you'd go over the 10 minutes that comes on a new TF.
If you really don't want to carry it home, by all means drop it in the trash or leave it behind somewhere. 20$ phone & 20$ service card. If you really can't risk keeping it, minimal loss.