A good deal Yu-Gi-Oh! players have trouble getting "rare" cards for their decks. Rare cards can often only be found for ridiculous prices, so if you don't have the money, you can't play the game. This can be discouraging, even to the point of giving up on the game entirely.
There's almost nothing I hate to see quite as much as this. That's why I've made this section: to explain to you how these "rare" cards may not be as far out of your reach as they seem to be.
First of all, many of the playable rare cards can be found in Structure Decks! If you haven't heard of them, they are pre-made decks that come with 40+ cards and are roughly based on one of the Yu-Gi-Oh! character's decks. There are 4 decks: Pegasus, Joey, Kaiba, and Yugi. Each deck has it's own different cards. I won't tell you exactly what is in these decks, but if you do the proper searching online, you'll find out easily.
Here are a few teasers. They are intended to make your mouth water, and prove to you that these Structure Decks actually contain good cards: Magnet Valkyrion, Blue-Eyes White Dragon, Blue-Eyes Ultimate Dragon, Magical Silk Hats, Penguin Soldier, Fusion, Mirror Force, Raise Dead, Android Psycho Shocker, Change of Heart, Sacrifice, Thousand Eyes Sacrifice, Black Magician, Magician of Black Chaos, Time Wizard, Thousand Dragon, Red-Eyes Black Dragon...is it clear yet?
These decks can be found for fairly low prices, and the cards inside more than make up for the prices you'll pay for the entire deck, which ranges from $10 to $40, depending on your source.
Speaking of sources, you need to have good ones. Often the cards you want will be on Ebay or other auction sites, and they may not be as expensive as you would expect. If you're too young to run an Ebay account, ask your parents or an older sibling to help out. Odds are that they'll notice your devoted commitment and help you out.
Additionally, searching the internet can yield interesting results. There are tons of sites have Yu-Gi-Oh! cards, and they're all dying to sell them to you. If you shop around, you'll be sure to find the lowest prices for the cards you want.
However, what if you just can't find a certain card? Many of the older promo cards can be difficult for newer players to find, but if you're willing to pay a price, you can get them. You might actually be surprised at how cheap certain cards can be, and you'll probably find them if you shop around online.
To make your search easier, below I've included some of the sites that sell Yu-Gi-Oh! online. I've skimmed the surface of these sites to see what they basically offer, but only you know what you're after. I recommend ignoring my descriptions of the site and probing them on your own to get the absolute best deal on what you want. However, don't limit yourself to these sites if you want to find the best deals around!
Do the best you can in finding the cards you want, but if all else fails, send me an email. If there's a way that I can help you locate a certain card, I'll do everything that I can to do it, because I want everyone to be able to enjoy this game just as much as I do. Good luck finding your cards!