I found a few photos with wallpaper murals on the walls that had a tropical theme:
|amy lau design|
And nothing says tropical like canopy beds with netting for that girly tropical touch...
And finally, a little over the top - the treehouse bed:
Ricci, I hope this gives you some ideas.
For everyone else - I have a huge stash of kids' room photos (thousands...) and sometimes I have a hard time coming up with post ideas (believe it or not) so feel free to email me or leave me a comment of photos you'd like to see.