Hello,
I have a Green Basilisk, it's about 4 months old right now so it is difficult to tell whether it is male or female. The biggest difference between Brown and Green is color. Males of all 4 types (common basilisk, red-headed basilisk, green (double crested) basilisk and the central american basilisk) have pronounced crests on their heads and back. Green basilisks look very similiar to what a "dragon" would look like. Very cool, that's for sure.
Basilisk care is very similiar to that of a Water Dragon. You can find plenty of care sheets on them if you google green or brown basilisk. I purchased mine at LLLReptile (online). It arrived in perfect condition and I couldn't be happier with my purchase. Check them out for prices.
Take care,
You will be happy with any of these guys, they look amazing!
This is mine MALICE.