To prepare your rod for fishing, you first want to make sure your string is fairly new, and wont break when fishing. the best way to do this is to take about a foot or so of string out and try to...
you can only get one fishing rod. you get it from collin's dad in the begining. (but i forgot how. honestly sorry!) you can go lure fishing at the fishing hole too.
all you have to do is go to the blue mushroom house with the pond on the outside (just follow the path). the little elf-thing will sell it to you for 1000 dollars