The Rhyme Scheme

You find a strange note in Sonata Town, that promises a reward if you manage to solve all the riddles.

First riddle:
Greeting finder, greetings friend!
To make you rich, do I intend.
Find my clues, and heed them well,
Seek the riches where they dwell,
And you Shall thank me in the end.

A road twixt pines and cascades tall
Journey's start, but not for all
Wooden bridge, some stairs, but see
Stop halfway and check that tree!

The second riddle goes like this:
Well done my friend, well done indeed,
For you to see where these notes lead!
Proud am I of your hard work,
Let's hope you won't the next one shirk!

Where nuggets gold in tall stalks grow
And rumours tell of things below
In a hole, next to one more
A stone by two has things in store

The third riddle:
My friend, you did it, just like that! Are riddles things you excel at? How proud I am, but allow me, To increase the difficulty...

Gas lamps found on three of six
Giants slain in place of bricks
Two shine light on written word,
Step right up and check the third!

The fourth:

Where feet sink low and lights raise high
And giants, hollow, dead, stand by
A question asked while neath the screen
Refuse it in the circle green