No, it's not possible. But if can always catch a Pidgey or another low level pokémon you don't care about and trade the item with it.
some items are used during pokemon trading.
Yes... But it wouldn't be brand new or anything. You would have to either A pay for someone to get the requested pokemon and then purchase it from them OR "buy" those requested pokemon off of someone else's game (through trading).
Unfortunatly, the only way todo that is clonig Pokemon, trading, and a way that destroys the game. SORRY.... Or, Just clone the Pokemon with the item you want cloned, then release the cloned Pokemon if you don't want it
Oh, dude, the trade stone location in Pokemon Glazed is at the Goldenrod City Department Store. You can find it on the fourth floor, just hanging out with all the other cool items. So, like, if you wanna evolve your Pokemon through trading without actually trading, that's where you gotta go.
Yes, it is possible to trade items in Pokemon Pearl but, this is only allowed if you trade the item when it's attached to a Pokemon. If you are trading with a friend and don't want him to have your Pokemon just trade back.
The barter system
The Metal Coat is used for giving to your Pokemon (such as either Onyx or Scyther) and trading it (it would probably be best to trade with a friend though); because as you probably already know some Pokemon evolve by trading or giving them items then trading them.
somehow
a lot and most need certain items like syther needs to hold the metel coat and be traded where as kadabara just needs to trade withput any items but there are loads of Pokemon which need to be traded a LOT
By trading with held items. Have it hold a Deepseascale for it to evolve into Gorebyss, or a Deepseatooth for it to evolve into Huntail.
it matters what Pokemon you mean. Most Pokemon evolve by leveling up, others with stones and items, some by friendship or condition (some at certain times), and still more by trading!
Anville town at weekends is a great place for trading items, and The Riches house in Undella town trades items from the Abysall ruins for money.