In 22 years of playing tennis tournaments and leagues, I have won about 50 plastic trophies, 5 or 6 keychains, a few ribbons, and numerous glass cups or bowls... and a few other trinkets like water bottles, towels, sports bags, or even a Nike watch. In addition, most tournaments give away t-shirts to all of the participants.
In USTA League play, I have only advanced to sectionals once... this year. We won a cheap bathroom accessories bag that says "2006 USTA Local League Champion", and we got a t-shirt at sectionals that says "2006 USTA Sectional Playoffs". Pretty cheap compared to the gigantic trophy and ornate keychains I've won with the city league team I played on several years ago...
Anyway, the total value of all the stuff I've won in tennis tournaments probably doesn't add up to more than $500 in all that time. On the other hand, I started playing golf a few years ago, and with less than 2 years of play, I won a total of about $1,000 (in cash, gift certificates, or quality merchandise) playing various tournaments... and that was with a 14 handicap!
(If you want nice prizes, it seems golf beats tennis handily... but tennis is a lot more fun in my opinion.)