what are poeple using to master these days..??

IMO,
nothing on the master buss, 
for mixing,
is the best thing when you are really learning your craft.
 
once you are there,
having a nice 2-bus compressor on the master,
set very lightly, and mixing into it from the beginning of mixing sessions,
will provide a nice 'set' for the entire mix sound.
(this is what i do now.)
 
 
MASTERING:
when I master my own material,
i bounce to 2-track and put that into wavelab and master there.
i use very little,
maybe a 10 band eq,
linear phase,
and a linear phase multiband,
again, set very conservatively,
and then a brickwall limiter (i use L2, and dither with it.)
i tend to master individual files at separate times, and let each stand on it's own merit,
without really matching levels.
i find on my own stuff, i tend to match levels intuitively.
 
 
but if you are mastering in sonar,
you can do the same thing,
but for simplicity,
i'd still suggest bouncing final mix down to 2-track, and exporting that as a 24 bit file....
to bring into a new session of sonar.
a lot of folks will skip this step, and just do it all in the original song file,
but i like to make decisions final, and doing it this way helps me keep control and manage sessions the same across the board.
 
and if you are doing several songs at once,
pull all those into a new sonar file,
and give them their own stereo tracks,
and put your favorite mastering plugins on the sonar master, run thru those,
and bounce down each song to a new stereo file that can then be exported into a 'final' directory for burning to cd.
 
you'll have to have some software program that can burn red-book appropriate files to cd.