What is a good provider to get, if you want wireless internet anywhere you go?

[Nicole]

I need to be online at night a few days of the week. A few of those few nights, I work, I pretty much just sit in an apartment while the two handicapable people I take care of sleep. They are not allowed on the internet so its not a possibility to get internet in the home, so I want to get something that will able me to be connected when I need to be without paying an arm and a leg.
I know some about computers, but not really about bandwidth and such.
I dont mind making a monthly payment for the service either.

any help would be GREATLY appreciated, please contact me or leave a response if you have any questions