Nickstock98t/a

yeah so my car is originally from illinois. i drove it from there to san diego and went through some snow. and havent cleaned underneath. and i dont know if the previous owners drove alot in the snow and washed underneath or took any rust preventatives.
my car is a 98 t/a w/ 54k mi. the rust on the underbody isnt horrible or bad, its no where near that, i just want this car to be near perfect condition. so if you guys know any steps i can take or know any shops here in so cal/san diego that can help me out and do a great job without ripping me off and being redicously expensive, please let me know and i will owe you one!

thanks!!