Oh god,
When selecting a college me and my family made it a priority to completely avoid these issues altogether. I made it a top priority to select a college where I had access to gender neutral housing. I actually turned down all in-state public schools due to this and went for a more expensive out-of-state public school. I kinda wish now I went for a private one that had a gender neutral option that was willing to give me a substantial scholarship as I'm now in a bit of debt, but meh, it is what it is.
The definition of gender-neutral housing can vary, but generally it has at least the following.
1. Access to a non-gendered bathroom/shower (either private or public single-occupancy)
2. Single housing or housing arrangements where gender is disregarded.
If gender isn't disregarded in the actual rooms, a non-segregated floor plan also makes things easier.
Or alternatively, you can try to get them to let you live off-campus. Your options are of course much more flexible in that setting.
Me and my parents were able to get these (recently constructed) arrangements by speaking to the school's LGBT center for advice on approaching housing about it. I didn't need any letters or anything, they just went ahead with it and I got a single room on a floor with single-occupancy bathrooms.
But ofc YMMV depending on the college you're actually going to.
I'd otherwise consider getting that letter and changing your gender marker, it might help if you want to live in a dorm with a male student.
As for literature, I got advice about various colleges from the Advocate College Guide For LGBT Students, your college may not be in there though.
