Ok laddy, here be where yee get yer upgrade.
After you are done with Nuke School you are assigned to a sub or a carrier(Staff pickup is whole other ball of ear wax). Now the "wonderful" locations for each is varied.
Carriers: Norfolk, VA San Diego, CA Bremerton/Everett, WA and Yokosko, Japan. (there is talk about moving one down to Mayport, FL but nothing certain.
Submarines: Norfolk, VA Groton, CT Kings Bay, GA San Diego, CA Bangor, WA Pearl Harbour, Hawaii and finally Guam.
After you do 3-5 YEARS on a sub or carrier then you are eligible for "shore duty" Generally nuke shore duty consists of the following:
Instructor tour at NNPTC in Charleston, SC
Instructor tour at NPTU(if you can call this shore duty) in Charleston, SC
Recruiter(just about anywhere in the US is available most of the time)
IMA shop: this is where you work in a shop fixing other ships. (most major ship ports such as San Diego, Norfolk, etc)
Some other "general" shore billet such as Boot Camp RDC, some gopher in D.C., etc. These are very seldom filled by nuke enlisted.
There you go.