I had a similar issue in the first week after I bought my Mk3, and changing sparkplugs and leads did the trick. Try and get the right NGK BKR5EKU sparkplugs if you're replacing them (apparently the copper ones are best if you can get them, but Supercheap could only get the platinum), because they have a different design, and perform a lot better than the normal type ones I put in first.
The sparkplug tool should work fine, you need to put it over and twist it a bit and it locks into place, and you can pull it out... you might have to play around a bit to figure out, but it's not just a grabby thing, despite how it looks. But some leads don't have the right design for it to work, for instance the Champion ones I got from Repco are like this... and I don't know how the hell I'm going to get them off next time without breaking them. Lesson to be learnt: get the OEM leads (Beru)!
I think the platinum NGK plugs cost me about $20-25 each, was around $120 all up... Copper ones shouldn't be anywhere near that though.
Leads were something like $195 but they marked them down from like $410 because the guy thought that was a bit steep

but I'd definitely look at ECS Tuning or contact VW dealer about getting OEM ones.
Here's a handy video:
https://www.youtube.com/watch?v=4iu9BFLOHzQ
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