Missions & Complexes

I dont kno which mission corp better, I just kno Republic Fleet , but simily no any good agent in high-sec.

They said COSMOS Agent better
wanna kno how to search them. BTW they all in high-sec? and wut ships are used for running them?

Republic Fleet has a pretty good LP store.
http://www.ellatha.com/eve/lp/Republic-Fleet

To find available agents, use the in-game Agent Finder.
http://wiki.eveonline.com/en/wiki/Agent_Finder

Some helpful guides:
http://wiki.eveonline.com/en/wiki/Agent
http://wiki.eveonline.com/en/wiki/Mission_guide

There's 3 different standings that govern access to high level agents. If any of those 3 standings drop to -2.00 or lower, you can only access level 1 agents. If standing for that level 1 agent drops below -2.00, no more access with that specific agent.

Faction = high standing allows access to all Agents in all Corporations within that specific Faction.
Corporation = high standing allows access to all Agents within that specific Corporation.
Agent = high standing allows access to that specific Agent.

To access agents above level 1, you need to build up standing, either Corporation or Faction. Corporation standing is easiest to gain. If using Corp standing to access higher level agents, the Faction needs to be above -2.00 standing.

Level 2 = +1.00 standing
Level 3 = +3.00 standing
Level 4 = +5.00 standing
Level 5 = +7.00 standing

Training up various Social skills will help a lot. They will modify your Agent, Corporation and Faction standings. Connections, Social and Negotiation skills are the main ones to train. Train Diplomacy to help repair negative Faction standings.
http://wiki.eveonline.com/en/wiki/Item_Database:Skills:Social

Connections skill will raise your current positive standings with Empire. (4% per level)
Criminal Connections skill will raise your current positive standings with Pirate. (4% per level)
Diplomacy skill will raise your current negative standings with all. (4% per level)
Social skill will increase the amount of standings gained for completing missions. (5% per level)
Negotiation skill will increase mission reward and agent effective standing. (5% per level)
Fast Talk skill increases amount of Security Status gained for killing single most highest bounty Pirate NPC every 20 minutes. (5% per level)

Three different skills increase amount of Loyalty Points gained for completing missions per specific Agent Division. (5% per level)
http://www.eveonline.com/devblog.asp?a=blog&bid=909

Security Connections
Distribution Connections
Mining Connections

Event Agent missions will quickly increase Faction standing.
http://wiki.eveonline.com/en/wiki/Event_Agents

Just remember that completing Event Agent missions will incur both positive and negative Faction standings towards all Factions. Most Event Agent missions can only be completed once in the life of the character. Cosmos Agent missions are tougher than regular missions, like 1 level higher. Basically a level 1 Cosmos mission is equal to a level 2 regular mission. It's a good idea to be prepared (skills and ships) before working the level 2 and higher Event Agents.