Why don´t you insert it directly into the item_db2 sql table?
IMHO its the easiest way to go.
Just get MySql Workbench and make a connection to your sql server. Then edit them directly in workbench.
But if you wanna do it your way just make a sql script like the official ones:
#
# Table structure for table `item_db2`
#
DROP TABLE IF EXISTS `item_db2`;
CREATE TABLE `item_db2` (
`id` smallint(5) unsigned NOT NULL default '0',
`name_english` varchar(50) NOT NULL default '',
`name_japanese` varchar(50) NOT NULL default '',
`type` tinyint(2) unsigned NOT NULL default '0',
`price_buy` mediumint(10) unsigned default NULL,
`price_sell` mediumint(10) unsigned default NULL,
`weight` smallint(5) unsigned NOT NULL default '0',
`attack` smallint(3) unsigned default NULL,
`defence` tinyint(3) unsigned default NULL,
`range` tinyint(2) unsigned default NULL,
`slots` tinyint(2) unsigned default NULL,
`equip_jobs` int(12) unsigned default NULL,
`equip_upper` tinyint(8) unsigned default NULL,
`equip_genders` tinyint(2) unsigned default NULL,
`equip_locations` smallint(4) unsigned default NULL,
`weapon_level` tinyint(2) unsigned default NULL,
`equip_level` tinyint(3) unsigned default NULL,
`refineable` tinyint(1) unsigned default NULL,
`view` smallint(3) unsigned default NULL,
`script` text,
`equip_script` text,
`unequip_script` text,
PRIMARY KEY (`id`)
) ENGINE=MyISAM;
# Items Additional Database - Custom Items go here
#
# Structure of Database:
#REPLACE INTO `item_db2` VALUES ('ID','Name','Name','Type','Price','Sell','Weight','ATK','DEF','Range','Slot','Job','Upper','Gender','Loc','wLV','eLV','Refineable','View','Script','OnEquip_Script','OnUnequip_Script');
#
# THQ Quest Items
# =============================================================
# REPLACE INTO `item_db2` VALUES (7950,'THG_Membership','THG Membership',3,NULL,10,10,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL);
And execute it in myphpadmin. (without the "#" in front of the items ofc)
Look at this thread from Mooka about PvP Master Ultimate: http://rathena.org/board/topic/53391-pvp-master-ultimate-v130/
There is a video of the script + execute method.