We had a father that was just an outstanding photographer and took action shots throughout the year of the team. We turned them into a bound book with a printed roster and notes from the boys. The company we used was
http://www.mypublisher.com and the turn around time was just a couple of days. It was a great price, a beautiful book and well received. It made a nice coffee book.
Then we took the same digital pics and then made a personal dvd for the coach and team (not the one they use at the banquet) but just a more personal one to the coach. Very easy to do with home software and downloaded music.
Another idea, but one I did for my parents but would work for this is get a very nice box with a lid, could be silver, crystal, wood and then take paper, like something a fortune cookie would be written on but just a bit bigger. Then on each piece of paper write personal thoughts, memories, phrases, plays, stories and/or dates/locations that would remind him of a great memory. Then fold each sheet individually and place them in the box. If possible you could have his name engraved/etched on the box.
The coach can then open the box and take out each sheet and read them at his leisure. It is very personal and we all forget things throughout the years and this is just one way to bring those thoughts/memories back. When I did mine there was about 100 pieces of paper, I just kept a log by my bed and when I would think of something I would job it down it was yrs of family/personal memories. My parents would just sit around and open the box read one and it was just a great trip down memory lane.
These ideas can be a individual gift as well as a team gift. The book can be from your family and through out you could have captions/info. that is from you son.
And of course, anything personal for the players is always nice.