Python wrappers to WCSLIB are provided by
Java is supported via
Recommended WCS-aware FITS image viewers:
both handle 2-D images.
Currently (2013/01/29) I know of no image viewers that handle 1-D spectra properly nor multi-dimensional data, not even multi-dimensional data with only two non-degenerate image axes (please inform me if you know otherwise).
Pre-built WCSLIB packages are available, generally a little behind the main release (this list will probably be out-of-date by the time you read it, best do a web search):
Bill Pence's general FITS IO library, CFITSIO is available from http://heasarc.gsfc.nasa.gov/fitsio/. It is used optionally by some of the high-level WCSLIB test programs and is required by two of the utility programs.
PGPLOT, Tim Pearson's Fortran plotting package on which PGSBOX is based, also used by some of the WCSLIB self-test suite and a utility program, is available from http://astro.caltech.edu/~tjp/pgplot/.