Here we go, like what eleveninth said:
Red Dot Photo (Singapore) - Products
S$300 will not get you a decent slider that won't really jerk. You can forget about DIY unless you're really good, and you can forget about glidetrack because those probably will last you a year or 10 shoots before the plastics wear out and you're left wobbly.
You can check out my video titled "Reunion" in the showcase subforum for examples of how I use the slider. I've got a review coming up, just haven't written it yet.
Cheers,
Zexun