Where do I buy clothes for my avatar? when I go to the avatar shop they only sell the clothes for diamonds.... Is there a clothes shop were i could buy clothes for gold?
also while I'm at this question is there a item/shop search anywhere?

Clothes for your avatar can be found in your Wardrobe. Some are free, some are unlocked with AP points that are earned by doing a ton of things in the game (battling, breeding, etc.)
There are also outfits. Outfits are just as they say; entire outfits with everything. You can find some of these as you explore as part of the storyline, others can be bought in the diamond shop with diamonds as either Monthly items or regular items; and some are found during events and either can be found as a drop from bosses, or bought in the Trade broker for gold. Right now, some can be bought with chocolate coins, a special fall event only currency.
There isn't a shop search, but it's broken down in the Trade Broker by item type, and pretty easy to just browse through, there aren't that many items for sale at any time.

http://www.sylestia.com/trade/tradebroker/
This is the trade broker. If you look, there's a drop down menu; it says "Relic" by default. If you go to the bottom, it lists the Avatar items that are for sale.

I've sent you a couple things to get you started and as a welcome to the site.
Welcome to Sylestia! I'm sure your avatar will be looking amazing in no time at all.

Thanks :)