If you can't work a traditional job because of disability maybe you can do something else. Try teaching yourself coding and you can make money from home.
http://www.codeacademy.com http://www.codecombat.com http://www.skillcrush.com
I switched to a weird keyboard a few years ago, and keybr helped me out a lot to get my accuracy back.
They track both speed and accuracy, so you can slow way down, perfect your accuracy, then gradually speed back up again.
That works well for plain words, but for more programming-specific accuracy (special keys etc) I found it pretty helpful to run through several zones of CodeCombat.
I did it to pick up the syntax for a new language, but because you have to bang out similar code repeatedly and the levels are short, it ended up helping out my muscle memory quite a bit.
I'm in roughly the same situation as you, though my last programming experience was a mere nine years ago. The site that boxsalesman posted is one I'm going to check out, but I'd also recommend this site:
It's a great tool for actually showing you the results of various commands within the context of programming game mechanics.