I'm also a new owner and here are the first things I did (in order).
Check and repair (if necessary) Secondary water pump (LCR only)
Check Alternator Pulley for wear, I had to replace mine.
Fabia Rear wiper conversion (OEM is carp)
HIDs - I fitted 5000K and they're about right (not boy racerish)
Matching LED side lights for the HIDs
Aero front Wiper Arm conversion (a must - I'm still searching as they're rarer than rocking hrse poo)
I'm about to treat myself to some nice detailing kit after I get a few bits done on the paintwork. After that probably spruce up the engine bay with some shiney bits
Mine has Aero wipers on when I bought it, Thought they were standard?
Supra where did you get your HIDs from mate?
Nope, you're just one of the lucky ones!
I drove 400 miles in terrential rain soon after I bought mine and the standard wipers are about the worst of any car i've owned! Hence the mission to upgrade. I've emailed about 15 breakers on ebay today so hopefully one will come back with a set.
To add to the list above I've also purchased a cheap ebay cable for VCDS lite. Always worth knowing whats going on under the hood without paying stealer prices.
My advice to the newbies would be
Clean and reset throttle body
Check all boost and vac hoses
Clean MAF (not a must tho)
Clear air filter if open cone if standered get a nice new one
Change plugs and coil packs (coil packs always go)
New oil and filter
If you can take off sump and clean oil pick up as it's common to block and damage the head
Then
Get forge 007p diverter valve
Bypass N249
Replace boost and vac pipe with new silicone ones (kits available)
Coilovers
Downpipe
Turbo back exhaust system
Remap
Then have some fun