Which is the best playground for cockatiels?
http://www.amazon.com/JW-Pet-Company-Large-12-5in/dp/B000FHQKD4/ref=cm_cr_pr_product_top
http://www.amazon.com/JW-Pet-Insight-Activitoys-Birds/dp/B000MAJLY4/ref=sr_1_4?ie=UTF8&s=home-garden&qid=1271480150&sr=8-4
Or does anyone else have any other suggestions?
the second one id have to say.
yeah its simple, but cockatiels just love to perch.
they do also enjoy bells, and mine loves sitting up high 
if the playground is too congested its more likely they wont go near it.
making your own could be more rewarding but you could buy wood that is harmful to your cockatiel.
so id say go with your second website
all the best
x