What moblie service to get, part 2

[Mike]

I'm in New York City.  I need to switch plans this month because my 
uber-cheap prepaid service (ecallplus.com) is ending this month on the 
30th (It's TDMA!!).

I've been reading (and asking) here before about this, here's what I 
still don't get-

I know I need to do either Cingular or Tmobile. I'm going to do 
Cingular.  Two questions and a suggestion:

1. Do I need to do a service with a two year contract in order to get a 
SIM card?    I've read mixed answers on other threads here.

2. Do I need a service with internet access?  Some (one) of you were 
talking about using a service to "dial up".  Can the neo dial up an 
internet service the way a desktop modem can?  If so could I do a 
prepaid plan like this:

http://ecallplus.com/cellular/callplus-gsm.html

(or would I not get a sim card if it's pre-paid or what?)

http://lists.openmoko.org/pipermail/community/2007-February/003858.html

I also think the openmoko.com site should have information on services 
somewhere. It's such a fundamental question- "what services can I use 
openmoko with?"