I actually used to intern at a podiatrist office, PF patients were easily 30% of all the patients we saw. So while I can not claim to be a physician, I have a fair amount of experience with PF (I myself have also suffered from it over the years).
Best advice is to go talk to a podiatrist.
That being said - I can probably tell you most of what you will hear at a podiatrist office (assuming you don't have an extreme case). There are a number of actions you can take to relieve PF pain. The aforementioned frozen water bottle/roller/ball plantar massage is great before bedtime (or as needed for pain relief), you can use passive stretches while you sleep (its basically a boot that dorsiflexes your foot overnight), NSAIDs will help, but MOST importantly - make sure that you have shoes with supportive insoles that you wear as much as possible. I recommend not bearing weight at all without wearing support.
Note: supportive insoles do NOT include gel/comfort insoles (i.e. Dr. Scholls)
The custom orthotics are ideal, however not absolutely necessary for all PF sufferers. If you do pull the trigger on them, there is a very solid chance they'll make a world of difference for you (but you'll be at least $300 in the hole). You could quite possibly get away with some cheaper, supporting insoles. New Balance makes good replacement insoles, superfeet is good, a number of other companies make quality inserts.
If you talk to a podiatrist they may recommend cortisone injections at the proximal plantar fascia. If the problem persists, they might guide you toward shockwave therapy (serious $$$ though, and insurance won't cover it).
Lastly do NOT go barefoot!!! Worst advice possible. Anyone who tells you this regarding PF clearly has absolutely no idea of how to properly treat it.
PF sucks, and it can be painful for awhile - be diligent on treating it, and don't be afraid to go talk to a DPM about it.