The Celebi EX (141 / 149) card can be found in the Boundaries Crossed set.
Recently sold 7 times and based on those sales is worth around £20.11.
Currently, there are 11 open listings for this card on ebay.
This card sells in the range of £14.27 to £25.95, making it quite stable.
This Rare Ultra card was illustrated by 5ban Graphics.
The fact that it is a EX card makes it one of the more valuable cards.