where to find green dr. and Dryads

[HellHound]

Hi all, im playing a lvl 22 mage (may be 23 not sure...) and im going to Demonis (sp?) the army i have is horsemen, red dr. knights and both unicorns.
i have 4 green dr in my reserve (only have one slot open) and would like to exchange the red Dr for green but i have only found one place so far were i can buy greens and have used them all, also im out of dryads whitch i would like to use there also, and i only found one place to buy them at to, and while im at it, just were do you get the lake fairyes at? i have the ring that gives all females the +3 and am thinking about trying them to.
Thank you in advance for any help!