1. Try Spybot Search & Destroy as well. Adaware is great, but it's best used with Spybot as well, since one will catch most of what the other might miss.
2. If you look on ntsearch's website, there's something that's supposedly a removal tool for it. Whether you can trust it or not though, that's up to you - considering they've already decided to hijack your PC without your permission.
3. Check in Add/Remove programs for anything you're not sure what it is. Not all spyware thigns add an entry, but it's worth a shot.
4. Get Firefox or Mozilla and stop using IE completely - they're not exploitable like IE is, nor have security holes which allow dodgy things like ntsearch to hijack your PC in the first place