I've never played Gaia, but does it give you all those parts or do you have to make it yourself?
Gaiaonline at its core is a forums based game, earn gold for posting comments, playing games, and other activities. You can then go to stores to buy items, or the marketplace where there are tens of thousands of articles to choose from. Most items are released monthly and never sold again, and with a real virtual economy items can skyrocket in price. Learning to play the marketplace can make you a gaian billionaire. For instance, that Jack of Blades avatar would cost ruffly 2,000,000 gold pieces.
If you want to have fun making a character to see what it would look like, you can go to tektek.org. This is a separate website where you can make an avatar without buying the items.