Machiara's Army for Beginners (with Purchases)
I would start with three boxes of plastic archers and supplement them with command groups. You should also buy the boxed set of Glade Riders along with a Champion and a Standard Bearer; Glade Riders are one of the most important units in a Wood Elf army. Grab a Treeman because he's very expensive points-wise and will let you start fielding an army earlier.
You should also purchase the female Wood Elf foot mage; I think she's the best one. Finally, purchase a Tiranoc Chariot for some hitting power (paint it Wood Elf colors, there's a thread on how to convert one on page one of the forum) and a Warhawk Champion for your General. This will give you the following nifty 1500 point army:
(Your General name here)
Wood Elf General w/ 298 points
Sword of Heroes, Golden Crown of Atrazar, Magic War Paint,
Lance, Shield
Warhawk
"Scythes of Loren"
Wood Elf Chariot w/ 115 points
Scythed Wheels,
3 Crew w/
Lt. Armor, Shields
"Riders of the Meadow Glade"
Champion w/ 81 points
Hail of Doom Arrow
Lt. Armor, Shield, Lance
Elven Steed
5 Glade Riders w/ 223 points
Lt. Armor, Shield, Lance
War Banner
"Oakheart" 280 points
Treeman
"(Mage Name)," 181 points
Wood Elf Mage Champion
w/Skull Staff and Rod of Power
"Meadow Glade Crimson Company"
8 archers 135 points
w/Banner of Sorcery
"Meadow Glade Nightshade Company"
9 archers 99 points
"Meadow Glade Emerald Company"
9 archers 99 points