Have you started the game already? It is usually best to all artificer if you are going that route as other classes just kind of get in the way of the cool stuff you get from that class. If you want to get some factotum levels I would actually recommend being human and picking up able learner to get into chameleon (Races of Destiny), that would allow you to have some cool spellcasting abilities from any list and would give you the ability to do some nice item crafting things due to the floating bonus feats.