Yes, but not much.
Expanded Psionics Handbook p159 mentions the percentages of intelligent psionic items and references the DMG p268 for intelligent items and tables.
That section of the DMG sets a caster level requirement for intelligent items, as well as some gp values for intelligent item stats and special abilities.
Not mentioned is the following quote from the DMG p288:
INTELLIGENT ITEM CREATION:
To create an intelligent item, a character must have a caster level of 15th or higher. Time and creation cost are based on the normal item creation rules, with the market price values on Table 7–30: Item Intelligence, Wisdom, Charisma, and Capabilities (page 269) treated as additions to time, gp cost, and XP cost. The item’s alignment is the same as its creator’s. Determine other features randomly, following the guidelines in the relevant sections of this chapter.
Magic Item Compendium p232 stipulates that:
For the purpose of meeting item prerequisites, a character who has the Craft Psionic Arms and Armor feat is treated as having Craft Magic Arms and Armor. Likewise, a character who has Craft Universal Item meets the feat prerequisite for items that require Craft Wondrous Item.
If an item includes a spell prerequisite, but the effect of the item does not directly implement that spell, then a psionic power of similar flavor can be substituted. If the item replicates a spell effect, then only the psionic version of that spell or a psionic power that replicates the same effect can be used to satisfy the prerequisite.
This allows characters with psionic abilities to create or assist in the creation of magic items, however it also goes on to say:
If you are using the Psionics Is Different variant (EPH 65), then an item created by a psionic character using a psionic item creation feat would be a psionic item. The guidelines given above should be used to determine the psionic item’s feat and power prerequisites.
Thus any items (magical or psionic based) created by a PID-based character would be a psionic item, and in fact, that statement allows the conversion of many magic items in the game into psionic items... except for items with prerequisites that do not have a psionic analog (such as eldritch blast) or do not have a matching spell and power.
Finally, and the simplest, easiest, and cheapest method of creating an intelligent psionic items is to be a psion, erudite, or to take the psicrystal feat... as psicrystals are literally intelligent items.
Thus, there ARE rules for creating intelligent items, but they appear to be very unsatisfying to most. Many people want an explanation for how and why the item is intelligent and some seem to feel that it should cost extra.
Others do not like the randomness of the special abilities which apparently cannot be assigned on demand but instead are randomly rolled during item creation as per DMG p288. This means that the cost of creating an intelligent item cannot be determined in advance, and might wind up costing considerably more than the character budgeted.
Presumably, this also means that if the character does not supply said random extra cost, then the crafting would fail - and this might account for the dearth of intelligent items (less than 1% per sources).
As for the why, it is hinted in various books that intelligent constructs and other intelligent items use elementals trapped inside the item as the animating item-spirit. Eberron Campaign Setting expands upon this concept with their rules for bound-elemental vehicles, items, and feat.
Does that mean all intelligent items have trapped elemental spirits in them? Who knows, it doesn't really say. Probably not, since there are also powers like Steal Steel which allows the manifesting character to inhabit a bladed weapon and more or less exist as a magic (psionic?) item temporarily.
As a bonus comment, there were precise psionic intelligent item creation rules in 2e, (as well as rules for how to grant the abilities of psionics to other characters or NPCs), but those rules apparently did not make the transition to 3e.