Emilija mentioned in a comment a few things of note. One is that I think telling employers early is a good, good thing. It is also good to get things in writing. I cannot work without certain accomodations (basic things) and my last company let me have them for years, then started trying to back out and fighting me about it not being required that they accomodate, etc. It is, and if it's in writing they have no outs.
Vocational rehab is a state-funded program available to anyone with a disability. It's got different names in different states, but vocational rehab is the basic name. (I use vocational rehab here to help keep my state unknown). The purpose is to find ways for people with disabilities to work. In my case they are trying to find accomodations to help me meet job requirements I currently can't. They are also helping me to determine if it is appropriate for me to continue working in the environment I work in, or if I need to consider a change. If change is needed they'll help me figure out what else I can do. They will assist with educational needs, equipment, advocacy, education of the company, mediation, providing a caregiver to assist to meet needs, whatever is required to let people work.
The only requirement for assistance is a documented disability which affects your ability to obtain or maintain employment. In this state you can refer yourself or someone can refer you. I referred myself. I had to wait about a month for an appointment, and then I filled out a lot of paperwork and releases. My psychologist had to submit an evaluation which was kind of hard to read because he had to talk about my lowest and highest abilities, and it was scary to see how low I can go; in fact he marked that when ill enough I can be poor in all areas listed. I can't remember if anyone had to send something in; I did get something from my eye doctor because I have visual issues as well.
After that it's been a twisted path, but now we're on track and hopefully soon someone will know how to help me.