There are plenty of microSIM cutters for few bucks that will convert regular SIM to micro

There are even cutting templates for printout on the internetz... no need for spending money here...

But this is the US. they will probably ask questions, because you have to pay an extra here for smartphones that are getting attached to a plan. Are there feature-/dumphones available in the US that use microSIMs?

(btw, T-Mobile DE even charged me going from a 2001 SIM to a USIM in 2008)

OK, what if you want to use the SIM in a regular phone then, after it's been cut, what do you do?

See here
http://lmgtfy.com/?q=microsim+to+sim+adapter

Be careful though, some adapters are not suitable for some phones that take sims.

E.g.
N8 manual strongly recommends against people using a mSIM to SIM adapter, as you can risk damaging the internal connectors.
People still do it, but it's tricky, you have to be careful

you can get adapters that will make your microsim regular sim again

I have an n9 and I am on Pay As You Go on AT&T. Just went to their office yesterday and they refused to issue a microSIM. They said they can only issue microsims if you have a contract. I tried cutting the SIM card myself, but it was not recognized by the phone. I ordered a cutter which should arrive in about 5 days, and I'll let you know how it goes. In the meantime, I tried using a contract microSIM for an Iphone, and it works. It seems like the chip on the AT&T microsim and the AT&T pay as you go sim are slightly different in size - the pay as you go sim has a longer and slightly narrower chip. I really hope that when I cut it with the cutter, it will work. Otherwise, I'm screwed....

Different carriers can use slightly different 'standard' sim sizes (the important metallic part of the sim card). My experience was that the T-mobile (UK) sim was too large to cut without damaging the actual sim. So I had to nip down to the local T-mobile shop and they were kind enough to sell me a duplicate micro-SIM for £10GBP. In most cases the cutter option should work fine, I'm just saying be careful and take your time. :-)

Well just ask your carrier to send you a dual SIM.

When I bought my N9 here in The Netherlands, they gave me a microsim. By the time I put they sim back in my N900 (they needed the number) my tel# had been switched to the new microsim for my N9, I left thhe shop making a test call.

At home I called my carrier (KPN) and asked for a dual sim anormal sized sim fo my N900 with the same tel#. It cost me 30,= Euro's and they send a micro sim for the N9 as well, for some reason.

Received it two days later and replaced the micro for the N9 and the normal sim for the N900. First call actived them.
Of course only one sim works at the time.

This is 100% wrong. Do research before stating anything this wrong.

@YavkatA - you need to go to a full-blown AT&T store. They normally do not have PAYG sim cards in stock, but the larger, official stores do.