Depends what they are. Some Yu-Gi-Oh cards are worth a lot, some are worthless. It's absolutely impossible to estimate without knowing what they are.
Simple, go to Yugico.com, they are dedicated to price guides for yu-gi-oh cards
YuGiCo.com is quite a good site. It tells you the rarity and value price of all Yu-Gi-Oh! cards.
they are on the back of th epackage
you cant sell any yu-gi-oh cards for a full price unless it is in PERFECT condition. but if it is a rare card you are going to sell you can sell it on eBay for a good price.
many of the god cards you see for sale now are replicas or fakes so they can range from about $20 to $40 each but real god cards are normally around $50 dollars each yes that sounds about right i got my 3 god cards for £115 so they are about £40 each and yes £40 is $50
YuGiCo.com is quite a good site. It tells you the rarity and value price of all Yu-Gi-Oh! cards.
best price would be $10-15 in 6/16/11
It depends on if you have rare cards and how much you are willing to use as the base sales price. Also it depends on how much the buyer wants to pay, from there you and the buyer can figure out a good median price
Both the old and new Yu-Gi-Oh! cards can be played together.
40-60 Yu-Gi-Oh! cards = a deck
white bordered Yu-Gi-Oh! cards are called Synchro monsters. they are the featured cards in the new Yu-Gi-Oh! show Yu-Gi-Oh! 5D's and they need to meet special requirements to summon them.
Go to google shopping and look for the best price but check the shipping and handling or go to a hobby shop because you would get better cards