Was hoping some locals would give you advice, but like others I can only tell you how I would look for places to backpack in an area I haven't been too. I'd find an area I am interested and then start looking at maps.

National Forests are a great place to start:


sometimes reading about dispersed camping you can find places somewhat near a trailhead (many dispersed camping locations you can drive to, but not all.)


I try to find forest service maps to get an overview of an area and where places to hike/backpack.


Once I have an area I check out trail maps on:


I will also google trail names to see pictures and trail reviews.