Um...that would be a scam.
Definitely stay away from that stuff.
It's not hard to get multiple 70's if a person just plays a lot and learns to level efficiently. It gets easier if you have 70 friends or your own 70's. My wife just broke 50 on her Paladin yesterday after a little over 2 weeks of play. She gets a lot of instance runs from 70's.
As far as group roles... It breaks down to 3 main roles. Tank, DPS, Healer.
Tank is generally the highest stress role with low tolerance for mistakes. The only classes/specs that perform the role well are Protection spec Paladins, Protection spec Warriors, and Feral spec Druids. The Feral spec Druids have an advantage that they can switch to cat form and switch to some alternate pieces of gear and do pretty good DPS since the Feral talents are mostly dual purpose. Definitely want to get Omen Threat Meter mod.
DPS is generally the lowest stress role. It mostly consists of learning to play a class effectively, and staying out of trouble. The main thing to watch out for is not to pull aggro from a tank. This makes a threat meter completely necessary (Omen)… Every class can perform a DPS role with the right spec. Some can do it in multiple ways with different specs. Each class can provide certain types of additional utility beyond just hurting stuff…typically in the form of buffs, crowd control, and more. Mages sheep mobs and conjure food. Hunters can trap. Shadow Priests can shackle undead and regen mana and health for party members. Rogues can sap. Warlocks can banish elementals. Druids can sleep animals. It goes on and on…most classes have several things they can do or provide. Groups generally need more DPSers than anything else, but sometimes it can be hard finding a group as one because there are a lot of them playing. Mage is a good and fun DPS class to start with because Polymorph is one of the most usable CC's and is easy and reliable to use. They are also on the high end of damage output capability. Hunters are also a good starter class in general, but trapping for group play is a lot more complicated and dangerous than sheeping.
Healing is somewhere between the other two on stress level. It's normally the easiest role to get into groups with. Every class that can heal, can potentially do it very well nowadays. Priests have the most robust and well rounded healing ability set, but each of the other healing classes has something killer that Priests wish they had. Druids have Lifebloom, an array of instant cast heals & HoT's, and a battle resurrection. Shaman's have Chain Heal, an array of useful totems, and can rez themselves. Paladins have incredible sustainability with Flash of Light spam and ability to at least temporarily save themselves.
Since you already have a Paladin, I would recommend just continuing to level, probably as Retribution (you can get Crusader Strike at level 50 if you spend your talent points right) until you get to 70. Leveling as Holy or Prot will go more slowly and painfully for the most part. You will still be able to do basic tanking, but stay away from anything difficult for your level. If you save up any +healing gear and stuff with stats that help your mana pool, you can also do some decent healing if you need to. Keep in mind this gear can be Cloth, Leather, and Mail since you can wear it all and are just looking for best healing stats. Armor doesn't matter as much when you are standing in the back healing. Once you get to 70, then look at respeccing to a Holy spec to greatly increase your healing ability. At that point, you will be looking to PvP for gear, run instances and Heroics for gear, and start raiding in Kara / Gruul's depending on the size of your guild. I would recommend a 41/20/0 PvP based healing spec as it happens to translate into PvE healing almost as well as a pure raid spec and works a lot better for PvP. If you get enough money, you can just pay the 50 gold max-out and respec whenever you feel like. Paladin healers are very popular right now and easy to play effectively. They get used a lot in raids for their lasting power. They're also great PvP healers because of their survivability.
If you'd rather do a DPS based role, I'd recommend starting a Mage. They're a ton of fun and one of the more sought after DPSers…free food and the ability to portal yourself from city to city is a huge perk, too. They can also level extremely fast if you learn the AOE mob farming technique…as well as the travel time saved. If you'd rather do melee DPS, I'd recommend starting with a Rogue. Notice that no one will ask you to tank or heal on either of these classes.
