The vehicle you're talking about was marketed by MGA Entertainment as a Tarantula, sold in 2004.
here's a link. if that doesn't work, try this one. http://tinyurl.com/2gdkav
If you click on their product support link, you can email the parts department and ask for a remote. Make sure you get the right frequency. But they'll email you back, and tell you to send them a check for $5 S/H and its a done deal, they'll mail it back to you.
Funny running across this post. I actually found one of these, a brown one, that someone had tossed out for trash pickup here in Central Texas. I tried to search for information on it, and strangely enough, the only thing i could find, using the little bit of information on the car itself, was your post asking for this. After fiddling around with the search criteria, i finally found a few forums from Australia, where they apparently like to use these RC cars to make Robots. Found the product name that it was sold as, and that actually let me get the parts ordered.
Thankfully the car i picked up had a battery in it... i found a charger from a Tyco that works fine, and boom.. now that i've got a remote, my kids are enjoying the tar out of the vehicle. not all that fast, but lots of torque
Hope this helps!!!