wgrib2 is a swiss army knife for grib2 files. You can use it inventory or extract data. You can do basic database operations and other nifty things.
GRIB-2 has arrived and has begun replacing the the older standard GRIB (GRIB-1). Since GRIB-2 can reduce the file size by upto 80% (NAM, JPEG2000 compression), converting to the new standard may be faster than some expected.