First off, welcome to the game!
As for prime stats:
Mercenary - STR
Swashbuckler - DEX
Barbarian - STR
Priest - WIS
Paladin - STR
Hellion - STR
Shaman - WIS
Rogue- DEX
Scout - DEX
Bard - CHA
Sorceror - INT
Warlock - INT
Necromancer - INT
As far as INT, WIS and CHA - INT is of utmost importance to all spellcasters, as more concentration allows you to hold more spells, an. WIS is important as it determines your mana/mana regen (And also helps with will saves) but it is not as important as INT, especially since you can train mana separately from wisdom for each class, which adds to both your base mana pool and to your mana regen.
Charisma is VERY important for sorcs, necros and warlocks, but it is not as integral to most other classes: One of the biggest reasons for this this is that when you order a pet, follower, charmed person, animated undead, tribunal guard or anything that you can control to perform some action (Order all dirt Seago, order all bash Caquartien, order all rescue xxx, etc.) your character is actually prevented from performing any other commands for a period of time dependant upon your charisma. This lag can range anywhere from slightly less than a combat round for the most dynamic characters to almost three combat rounds for the abysmally repulsive, and those precious combat rounds can make a huge turning tide in a PvP or PvE scenario. Conversely, charisma is not as important for priests, shamans and paladins, because unlike sorcs (charm person, which is also affected by CHA directly in success rate), necros (undead hordes to order) and warlocks (elementals to order) these casters have nothing powerful beyond storebought pets to order around to make a difference in combat. Of course, your innate charisma also affects your experience gain (And if you are playing a light-aura, requesting), which is a decent reason to at least put it somewhere in the middle of the road for a first character as well.
Bards and Swashbucklers also should have maxed charisma as that directly affects their most powerful abilities (songs and taunt)
Other than that, I do encourage you to ICly find characters who are willing to help out and interact with yours, and learn things such as places to train and where to find useful equipment that way. At the very least every high level character should be able to tell you where they personally trained.
Oh, and you should also make liberal use of
this map, because it owns.