Got mine for free at some show. What I did was take a couple of those foam can cooler things, put velcro on the bottom and on each fender and stuck them there. Haven't fallen off. Got mine at a Black and Decker booth and they even match the tractor.
Check out the attachment. Hopefully you can see the water bottle in the holder. I use them to hold sunglasses, etc as well as fluids.
The white PVC pipes on the FEL are where my forks live most of the time I'm not using them.