These types of items are staples in D&D, and should be able to be implemented fairly easily, once the rest of the crafting system is fleshed out. Here is how I'd implement them.
Scrolls: Use the inscribe scroll feat, either giving it to all spell casters, or allow wizards to get it free and other spell casters to take it as a feat. Only wizards would be able to use it to add to their spellbooks, but other casters could use it to create scrolls of the spells they have memorized. With the feat on their hot bar, and the appropriate level spell inscription materials in inventory, they select a blank scroll (either purchaed from an NPC reagent seller or by disjoining another scroll) and click on the inscribe scroll feat. This brings up a window with the spells memorized to select from, then it asks you what caster level to make the spell (min lvl to cast the spell to max of your caster lvl). This would construct a scroll of xxxxx (xx lvl). If they are unbound, casters would be able to make a profit off of selling them in the AH, since they are used in crafting other items. If they are BtA, people would benefit from having a high level caster on their account. If BtC the character only would benefit.
Wands: Include shard recipes for 1st, 2nd, 3rd lvl shards of wand charging (wands can only hold up to 3rd lvl spells in D&D). Then combine the shard with a disjoined wand, and a stack of scrolls. Each scroll provides 5 charges for the wand (max 50 charges), and the caster level is the caster level on the scrolls. If you make it so craftable wands aren't destroyed when they reach 0 charges, the wands can be recharged by adding more scrolls.
Staves: Include shard recipes for 1st - 6th lvl shards of staff charging (Staves can hold up to 6th lvl spells in D&D). Then combine the shard with a disjoined staff, and a stack of scrolls. Each scroll provides 3 charges (max 30 charges) for the staff and the caster level is the caster level of the scrolls. If you make it so craftable staves aren't destroyed at 0 charges, then they can be recharged with more scrolls.
Daily use items: Include shard recipes for 1st - 9th lvl shards of daily use. Then combine the shard with the disjoined item and a stack of scrolls. Each scroll adds 1 daily use (max 5 charges), and the caster level is the caster level on the scrolls.
This would allow quite a bit of extra utility to the crafting system, and add a lot of the flavor of D&D crafting. All of these shards would be suffixes, making the items named wand of xxxx (xx lvl), staff of xxxx (xx lvl), item of xxxx (xx). wands would also be able to have a prefix, since they would be craftable now.