Ask that at your local store and all you'll get is funny looks. Ask that on Etsy and the possibilities are endless! (one more reason I love etsy)
Here are a few of the FABULOUS things I've gotten through Etsy trading:
Wine Stopper by DreaBunny: (custom made to match my kitchen...isn't she awesome?!)
Crackle Glass Purple Earrings by KSchaffter:
Fabric Covered Pocket Mirror by flirtbuttons: (Please note, flirtbuttons is not currently trading)
Etsy forums. There are numerous trading threads you can search through or add your name to.
Pluck Bracelet by relishdress:
Another way is to contact a shop owner directly. Read through the shop announcements, policies, and profile first. Some owners will state whether they are open to trades or not. Please be respectful and courteous when contacting shop owners. Not everyone likes to trade. Ask nicely and don't be offended or upset if they say no.
Some people do trades differently, but the most common way is to agree on an equal trade (example: a $5 item for a $5 item) and then purchase the items from each others shop but don't actually pay for it. Then send out your item! Oh, and don't forget to leave great feedback for your awesome new goodies!
I'm currently on the lookout for some cloth napkins, placemats, and a tablecloth to match my blue and purple kitchen. So...what can I get for 2 bars of soap and a washcloth? :)