hi
Dracoslay, for banners, I use Photoshop and for sprites I use pixlr.com/editor
as for your sprite, it's decent but there could be some improvements.
- the positioning is kinda weird, you want them to be on the same level most of the times
- the background should be transparent and so should be the sprites because then on non-white backgrounds the sprite doesn't look very good
take a look at these 2:
- smaller background
- transparent
- kinda on the same level
- smaller and transparent
- dragonite's pose really fits in well with the position
that being said, I kinda like the Gen 4 sprites because on
http://www.pokestadium.com/tools/sprites, they show the 2 different poses for dragonite which is great since people always use the bw sprites. anyway, hope i helped, good luck with spriting :]