[Rilgamon]

http://www.wowpedia.org/Widget_API#StatusBar

WoW offers a simple widget you can use.

local b = CreateFrame("StatusBar", "MyOwnStatusBar")
  b:SetWidth(100)
  b:SetHeight(20)
  b:SetPoint("CENTER",UIParent,"CENTER",0 , 0)
  b:SetMinMaxValues(1,100)
  b:SetOrientation("HORIZONTAL")
  b:SetValue(75)
  b:SetStatusBarTexture("Interface\\TargetingFrame\\UI-StatusBar")
  b:GetStatusBarTexture():SetHorizTile(false)
  b:GetStatusBarTexture():SetVertTile(false)