See the vignette for help.
Please get your own API keys at http://developer.nytimes.com/apps/register - you'll need a different key for each API.
I set up the functions so that you can put the key in your .Rprofile file, which will be called on startup of R, and then you don't have to enter your API key for each run of a function. Put these entries in your .Rprofile file
options(nytimes_cg_key = "YOURKEYHERE")
options(nytimes_as_key = "YOURKEYHERE")
options(nytimes_cf_key = "YOURKEYHERE")
options(nytimes_geo_key = "YOURKEYHERE")