Cheapest priced copy (Magic 2012): $0.39 at Card Kingdom, near mint, their price list as of .
Lifelink 
Enchantment — Aura · Common · Magic 2010 · #18
Enchant creature
Enchanted creature has lifelink. (Damage dealt by the creature also causes its controller to gain that much life.)
Legal inCommanderModernLegacyVintagePauper
Not legal inBrawlStandardPioneer
2 printings · $0.39 to $3.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Magic 2010 | 18 | Common | $0.49 | $3.49 |
| Magic 2012 | 24 | Common | $0.39 | $1.99 |
One ruling from Wizards of the Coast
- 1 October 2009The controller of the enchanted creature, not the controller of Lifelink, gains the life (in case they’re different players).