F.M.
Well next time you're at the dollar store, get a pack of circular metal Stove covers. Then you can take your magnetic letters and help him make words and sounds. The magnetic letters will stick to the circular stove covers.
If you bring him a dvd player, buy the movies from preschoolprepco (avail at amazon.com or preschoolprepco.com). They have "meet the letters" which is probably too boring/basic for him. "Meet the numbers" "Meet the sight words 1, 2, and 3" are all great. You can watch previews on youtube before you buy. Go to youtube and search "Meet the letters preschool prep co".
Get a pack of alphabet stickers. Let him peel the stickers off the paper (good practice) and stick them to a piece of paper (50 cent spiral notebook?) Then you and him come up with a word that matches that letter. ie: He gets a "p" Color it purple. Draw a picture of a pig. Draw a food with p - Pizza, peas, pickles....