Yeah, he needs some performance upgrades.
Ebay is usually the cheapest place.
AEM Cold Air Intake $130 or AEM Short Ram if you have deep rainy seasons where you live $100
H&R or Eibach springs $110 (he will need to do the washer trick and get an alignment)
1999/2000 Civic Si OEM rear sway bar $60
Energy Suspension polyurethane shifter bushings for manual transmission $15
NGK Spark plug wires $40 and NGK Iridium plugs part #ZFR5FIX-11 $25
Front strut tower bar $15-50 depending on brand/quality; it doesn't sound like he needs high performance so replicas are fine
Rear strut tower bar $15-50, just like the front strut bar
Gift Certificate at a detail shop $100
Gift Certificate at Tire Rack $100
Wheelskins leather steering wheel cover/wrap (makes the stock one look nice with a better, thicker grip) $40
Razo pedal covers $20-30
Type R replica black leather shift boot $25, ebrake boot $25, and arm rest cover $40
I highly recommend the Wheelskin. It can be as subtle a color as you want or as racey as you want. Yet at the same time, it makes a WORLD of different in the feel of the wheel. It improves it a lot and makes it feel almost MOMO-ish (a very nice brand that makes nice steering wheels).