As the saying goes...many way leads to rome..u can make art work from PC or mobiles
First u must download the tibiaME element and data..
TibiaME data (From wesley)

after download u can make the art with..
Pc u need sofware for editing pictures Like:
Photoshop
Corel draw
GIMP
Photoscape

then for mobiles only for symbian s60v2 (.sis)
Phyton 1.6
after download phyton..next
Image Designer
MBM Tools

for symbian s60v3 (examples n73)
first u must install the hack tools..
Hack Tools
Phyton
IDesigner

Then u can make the Arts..
thanks for da wesley the tibiame data :)