How do i get held items?

[Cleveland]

Other than from the battle tower

Anywhere else I can buy or acquire?

 

[Cleveland]

Is there a list anywhere of how/where to get items and what their effects are?

 

[Luminance]

The effect of helditems is the same as the original games at the 5th generation with B/W specs.

As for where to find them, I suggest keeping an eye on the Announcements and Changelog forums. We mostly post on our respective changelogs or grouped in one announcement.