How to prevent Stun?

[yonman17]

Are there any spells/items that prevent stunning?

[Azothath]

yes... generally Object Possession:N2-5, Skinsend:N2, and such (creature type: Object, Ooze, Construct, Plant, Undead). Bonuses start with Undead Anatomy 2:T5 (polymorphs aren't as effective).
AoN search stun

[yonman17]

Those are more personal changes that give you a template. Are there any spells that actually prevent getting stunned?

[Wonderstell]

There's the Padma Blossom which requires holding it and suppresses morale bonuses, but deals with Dazed, Stunned, and Confused for just 8000 gp.

[Mark Hoover 330]

Hard Headed gives you a bonus against being stunned. I'm not seeing a spell that removes Stunned though. If you can hire a 12th level paladin to travel with the party, the 12th level Mercy: Stunned removes the condition.

[Niemand]

failing the save for several death spells can permently prevent future stunning.

[ErichAD]

The bardic masterpiece Symphony of Sylandurla’s Ascent grants immunity to one of these "charm effects, the dazed condition, fear effects, magical sleep, paralysis, the staggered condition, or the stunned condition"

It also grants allies a new check to avoid the condition if they already suffer from it.