Noted. Thanks for the tips!
So i should build INT for my stalker?
Will i be able to reset my stat when i change job from thief to stalker?
Coz i need STR to get me to lvl 15, before i could purchase any mercenary 
As a thief/rogue, you'll want to level using your normal skills. Don't rely on Intimidate as a rogue because when a monster casts a copy-able skill on you, your saved skill can change. So it's not worth it to copy skills. After you transcend, and you get the skill Preserve, that's when you'll want to copy a skill from another player, then use Preserve to save it for 10 minutes. Just make sure to keep Preserve up or you may lose the copied skill.
If you go to http://irowiki.org and select "Classes", you can learn about general leveling strategies and what to expect. Just keep in mind, though, that some of the information on that site can be out-dated, especially the equipment, since we get new updates occasionally. You can also read about the mercenary system (the scrolls that you buy to summon mercenaries,) by clicking "mercenaries" under the "System" category on the main page.
And yes, you can reset your skills/stats. There's an NPC called "Hypnotist" in Prontera near the tool dealer shop. You can reset your stats and skills as many times as you want while your under base level 40. There's also a Hypnotist in the Eden group, first floor that can reset your stats and skills beyond level 40, but you can reset your stats and skills ONLY ONCE using that NPC. So if you put too much Int as a Stalker so you can level with a copied skill, or don't like how things feel, you can use that NPC to reset your stats and skills, even as a third class. There's other methods to reset your stats and skills beyond level 40, but they cost money and/or zeny, usually. You can read about them on irowiki as well.
