*delurking*
Sharifu's correct that Taka comes from The Lion King: Six New Adventures (TLK6NA). Also, like Sharifu, I found my set on eBay (sweet, sweet, addictive eBay). It should be noted, though, that MehndiX was kind enough to scan and upload the whole set onto her site -- http://www.nala.at -- for those who have not been so lucky as to find and purchase it. You have to register to view the site, but that registration is free.
Coincidentally, taka does not just mean "rubbish, trash, etc." It also means such abstract and unrelated things as "bolt of calico cloth". There are also the verb meanings of "to ask" and "to wish". My personal favorite is the verb taka shari, meaning "to defy, to challenge". Granted, the translation given in TLK6NA was that of "garbage", but I imagine that was at least in part so as not to confuse the kiddies with more...thought-provoking translations.
The fanfic Leo_the_Lion is referring to is "Pride Lands Generations" or "TLK Generations" (or something to similar effect, I can't recall it precisely off the top of my head), if I'm not mistaken. In the interest of stemming any misconceptions, Disney has only gone back as far as Mohatu (from the read-along book The Brightest Star), so any earlier "ancestors" are purely fan speculation.
Also, since I've seen the mistake a lot. Ahadi's queen is Uru, not Akase. Both Ahadi and Uru come from TLK6NA, while Akase was created by none other than Brian Tiemann for his fanfic "The Pride". The name was picked up and used in "Chronicles of the Pride Lands" (CotPL), from where it gained wide circulation. Similarly, Tanabi as Simba's son is a fan name that has gained wide circulation via CotPL. As Sharifu pointed out, Simba's son is Kopa.
It's probably also worth a mention that Ahadi's design is rather...debatable. In the text, he's described as being black-maned and green-eyed; yet in the illustrations, he's a Mufasa clone. I actually prefer the latter, myself, but that's another discussion entirely.
Lastly, I think, something needs to be said regarding the Taka-Scar debate. That is, there are those who vehemently swear by one name or the other only. In such instances, Taka is seen as the "sweet, good, innocent" side while Scar is, well, Scar. Many a flame war has been fought on these grounds. Ironically, this dichotomy of character is derived from his depiction in CotPL -- TLK6NA's Taka is by no means a wide-eyed innocent but a bitter, reproachful adolescent.
To which point, I do believe I've put in more than my fair two cents.