Pokémon Gold and Silver/Mahogany Town

When you first arrive, you won't be able to do much here. The house with the sign next to it is the mart but sells useless items as well as a few potions and PokéBalls. You'll find you path to the right blocked by someone wanting you to buy Rage Candy bars, and the Gym blocked by another person who wants you to go to the Lake of Rage. To progress any further, you will need go north through Route 43 to the Lake of Rage. Before you do, however, you might want to fly somewhere you can get some Great Balls from, as you have a battle with a very very rare Pokémon ahead.

Items
Considering the town is overrun by Rockets, you won't be getting anything free... the most unique item you can get would be is a Rage Candy bar, which is as strong as a potion, and costs as much as it (300). However, any items that you can buy that are really useful can only be obtained after you drive out the rockets, and that still will be a while...