Here's a link to any info that you'll need about shops http://db.gamefaqs.com/portable/gbadvance/file/final_fantasy_tactics_advance_shop.txt

Okay, here are all the items you can get in a shop.  They
are arranged alphabetically.  Each item also follows this
format:

Item name, item type, town where the item can be bought,
when you can buy the item.

For the town where the item can be bought, most items can
be bought at any shop.  These will simply be labeled all.
However, there are a few items that can only be bought at
a particular shop, and they will be labeled appropriately.

For when you can buy the item, stores upgrade their
inventories occasionally (see the Shop Upgrades section for
more).  Listed will be the number of the shop upgrade at
which the shop gets that item.  A plus after the number
indicates that the item can be found in a shop after that
upgrade.  For example, if an item is label 3+, you can get
it after the third shop upgrade.

There are some items you can get at the beginning of the
game, and they are labeled 0+.  So, an item labeled 0+,
like cuirass, is available the first time you enter
a shop.

If you're looking for a particular type of item (like a
saber), press [Ctrl] + [F] to search for a particular item
by entering the name/type of the item you want to find.

Here's the list:

Adaman Vest, cloth, all, 1+
Aiot Gun, gun, all, 0+
Air Blade, blade, all, 2+
Ancient Sword, greatsword, all, 1+
Antidote, item, all, 0+
Apocalypse, knightsword, all, 1+
Aqua Saber, saber, all, 2+
Ashura, katana, all, 1+
Atmos Blade, blade, all, 1+
Bandage, item, all, 0+
Barong, greatsword, all, 0+
Battle Boots, boot, all, 0+
Battle Mace, mace, all, 1+
Black Quena, instrument, all, 1+
Bless Staff, staff, all, 1+
Bless Staff, staff, all, 2+
Blue Saber, saber, all, 1+
Bracers, armlet, Sprohm, 5+
Brigandine, cloth, all, 2+
Bronze Armor, armor, all, 0+
Bronze Helm, helmet, all, 0+
Bronze Shield, shield, all, 0+
Burglar Sword, sword, all, 2+
Buster Sword, sword, all, 1+
Chain Plate, cloth, all, 0+
Chaos Rifle, gun, all, 2+
Char bow, bow, all, 0+
Circlet, hat, all, 2+
Conch Shell, instrument, all, 1+
Cranquin, greatbow, all, 1+
Cuirass, armor, all, 0+
Cure Staff, staff, all, 2+
Cureall, item, Baguba Port, 3+
Dash Boots, boot, all, 2+
Defender, knightsword, all, 2+
Demon Bell, instrument, all, 0+
Dragon Whisker, spear, all, 2+
Dream Claws, knuckle, all, 1+
Druid Mace, mace, all, 1+
Earth Bell, instrument, all, 1+
Echo Screen, item, all, 0+
Elixer, item, Cyril, 13+
Energy Mace, mace, all, 1+
Estoc, rapier, all, 1+
Eye Drops, item, all, 0+
Falchion, broadsword, all, 0+
Feather Cap, hat, all, 0+
Firewheel Rod, rod, all, 1+
Flamberge, rapier, all, 1+
Flametongue, blade, all, 2+
Fleuret, rapier, all, 0+
Force Rod, rod, all, 2+
Fortune Ring, accessory, all, 2+
Gae Bolg, spear, all, 2+
Garnet Staff, staff, all, 2+
Gauntlets, armlet, all, 0+
Glass Bell, instrument, all, 0+
Gold Armor, armor, all, 2+
Green Beret, hat, all, 0+
Guard Staff, staff, all, 0+
Hard Knuckles, knuckle, all, 0+
Headband, hat, all, 2+
Heaven's Cloud, katana, all, 2+
Hempen Robe, robe, all, 0+
Hi-Potion, item, all, 0+
Holy Water, item, all, 0+
Hunt Bow, greatbow, Muscadet, 6+
Ice Lance, spear, all, 1+
Icebrand, blade, all, 2+
Iron Armor, armor, all, 1+
Iron Helm, helmet, all, 1+
Jack Knife, knife, all, 0+
Jambiya, knife, all, 0+
Javelin, spear, all, 1+
Judge Staff, staff, all, 0+
Judo Uniform, cloth, all, 2+
Kaiser Knuckles, knuckle, all, 1+
Kard, knife, all, 2+
Khukuri, knife, all, 2+
Kikuichimonji, katana, all, 2+
Kotesu, katana, all, 1+
Kris Knife, knife, all, 2+
Kwigon Blade, blade, all, 2+
Lava Spear, spear, all, 1+
Leather Garb, cloth, all, 0+
Lionheart, knightsword, all, 1+
Lohengrin, knightsword, all, 2+
Longbow, bow, all, 0+
Mage Masher, rapier, all, 2+
Magus Robe, robe, all, 2+
Maiden Kiss, item, all, 0+
Masamune, katana, Muscadet, 9+
Mistle Robe, robe, all, 2+
Murasame, katana, all, 1+
Nail Bow, bow, all, 2+
Ninja Knife, katana, all, 1+
Ogun Blade, blade, all, 2+
Opal Helm, helmet, all, 2+
Opal Shield, shield, all, 2+
Osafune, katana, all, 1+
Paraiba Blade, blade, all, 2+
Partisan, spear, all, 1+
Phoenix Down, item, all, 0+
Platemail, armor, all, 2+
Potion, item, all, 0+
Power Sash, cloth, all, 2+
Predator, broadsword, all, 2+
Princess Rod, rod, Baguba Port, 10+
Pure Staff, staff, all, 1+
Ragnarok, knightsword, all, 1+
Ranger Bow, greatbow, all, 1+
Restorer, broadsword, Cyril, 7+
Temple Cloth, cloth, Cyril, 8+
Riot Gun, gun, all, 2+
Rising Sun, knuckle, all, 0+
Rod, rod, all, 0+
Rondell Dagger, knife, all, 2+
Round Shield, shield, all, 1+
Sage Crosier, mace, all, 1+
Samson Sword, broadsword, all, 1+
Satyr Flute, instrument, all, 1+
Scarab, accessory, all, 2+
Scarlette, rapier, all, 0+
Scramasax, knife, all, 0+
Seventh Heaven, greatbow, Baguba Port, 12+
Shadow Blade, blade, all, 1+
Shamsir, saber, all, 1+
Shortsword, sword, all, 0+
Sick Knuckles, knuckle, all, 1+
Silken Robe, robe, all, 1+
Silver Bow, bow, all, 1+
Silver Cannon, gun, all, 1+
Silver Sword, sword, all, 0+
Sleet Rod, rod, all, 1+
Soft, item, all, 0+
Spiked Boots, boot, all, 2+
Star Armlet, accessory, Cadoan, 4+
Stinger, rapier, all, 0+
Striborg, broadsword, all, 2+
Sun Blade, blade, all, 1+
Survival Vest, cloth, all, 1+
Sweep Blade, blade, all, 0+
Terre Rod, rod, all, 1+
Thorn Bow, bow, all, 0+
Thunder Rod, rod, all, 1+
Tiptaptwo, knife, Cadoan, 11+
Twin Bow, greatbow, all, 2+
War Trumpet, instrument, all, 0+
White Staff, staff, all, 0+
Windslash Bow, greatbow, all, 1+
X-Potion, item, all, 0+