For general gardening work I use Wilkinson Sword Grey Leather Gardening Gloves, which cost around $10 from the local DIY store.
Soldier 95 Leather Goretex gloves are a bit more expensive but are excellent if comfort, fit, durability and waterproofness is required.
http://www.militarykit.com/products/gloves/soldier_95_leather_combat.htmAnd for colder days Outdoor Design Winterflex inferno Goretex Gloves or Mitts are pretty good as well.
http://www.outdoordesigns.co.uk/products_gloves_winterflexinferno.html