Alternatives to standard keyboards are often recommended for ease of use. The keyboards may vary in size, color and shape. On-screen keyboards are an alternative to regular keyboards and are often used with switches to activate the keys.
Here are some resources of external keyboards:
Large key caps stickers are often used to convert regular keyboard keys to large print. This is available at Hooleon.
There are many varieties of ergonomic keyboards. This is user specific and should be recommended if it fits the need. Examples of some of these devices can be found at The Human Solutions website.
The use of the mouse as a pointing device can sometime be problematic for some users. Alternative pointing devices are often used to help with this. Trackballs, touch-pads and joysticks maybe some alternatives to consider.
School Health also has great alternatives for individuals with limited control of their hands.
JAN Network has a great list of equipment that allow individuals to use a computer through a variety of means (e.g. foot, eyes, etc.).