Simon,
I used managr.com all last season and found it really useful. Once I had entered all my players details I was able to select my team for each match and press a button to send each player a SMS message and then managr managed all of their responses so I could easily see who was available and who wasn't and any replies that they had sent.
Another good feature was being able to record holidays, etc. When I came to select the team for a match, any lad on holiday would be greyed out to remind me that they were unavailable. I also used managr to keep track of the players weekly match fees.
Having recorded the team, result and goalscorers for each match, at the end of the season I then bought from managr.com what they call a Season's Record Card for each of my players as a souvenir of a reasonably successful season. It shows each game, result, starters, subs and goalscorers and is done in your Club colours. The players really appreciated it!
I will definitely be using it again this season. Oh, and it was definitely free to use!