I have thought of this, and I think it is possible. The item creation feats simply require a caster level and the ability to cast the prerequisite spell once per day. Perhaps rules as written a spell-like ability does not count because it is not strictly speaking a spell. However, it's hard to understand why a spell-like ability couldn't charge a wand, for example.
My understanding of the theory of item creation is that the item requires the magic of a spell's effect, not the components of the spell. The exception would be the Scribe Scroll feat, which is explicitly a transcription of a spell's components. Since spell-like abilities have no components, they could not be used to scribe a magic scroll. Of course, D&D has no unifying theory underlying its magic system, so it's likely that WotC would officially say "no" to your proposal if asked.
Creatures with spell-like abilities are inherently magical, so it seems reasonable that one could enchant a weapon with an enhancement bonus by taking Craft Magic Arms & Armor and expending experience.
My feeling is that sorcerers should have spell-like abilities rather than spellcasting ability. (The difference may seem like semantics, but it is significant.) If you used such a system, sorcerers should still be able to craft magic items.
