"will any car fit any rim?"
no.
concerns are center hub bore, lug pattern, back spacing, offset, and fender/brake (vehicle equipment) clearance.
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DIY, (generic)
you gotta think ahead. whats your goal-look/profile, and on a truck, purpose. because different tires on a given wheel will also influence vehicle equipment clearance.
some solutions for body/equip clearances, other than oem configs are, spacers, lifts, cutting, or rolling fenders. you have a truck, so your options are plentiful. more so than a car. hub spacers are not advisable on utility vehicles.
so if you buy from the masses, you need to know your oem wheel aspects and compare them to the aspects of the would be wheel.
do not rely on a private party when they tell you a given wheel will fit. you will have no recourse if it doesn't.
so it's not always simple.
for a calculator and an explanation/understanding of what those terms mean, here are a few tools,
http://www.gtsparkplugs.com/WheelOffsetCalc.html
http://www.1010tires.com/wheeloffsetcalculator.asp
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best to go to a retail store if your not sure. they can give you options that apply to your specific vehicle. w/or w/o mods should you choose.
good luck!