PCPartPicker part list:
https://au.pcpartpicker.com/list/vN9LD2
Price breakdown by merchant: https://au.pcpartpicker.com/list/vN9LD2/by_merchant/
CPU: Intel - Core i7-8700K 3.7GHz 6-Core Processor ($508.50 @ Shopping Express)
CPU Cooler: Corsair - H100i v2 70.7 CFM Liquid CPU Cooler ($138.00 @ Shopping Express)
Motherboard: Asus - ROG STRIX Z370-E GAMING ATX LGA1151 Motherboard ($313.00 @ Skycomp Technology)
Memory: Corsair - Vengeance LPX 16GB (2 x 8GB) DDR4-3000 Memory ($271.00 @ IJK)
Storage: Samsung - 960 EVO 500GB M.2-2280 Solid State Drive ($310.00 @ Umart)
Storage: Western Digital - Caviar Blue 1TB 3.5" 7200RPM Internal Hard Drive ($58.50 @ Shopping Express)
Video Card: Asus - GeForce GTX 1080 Ti 11GB STRIX GAMING Video Card ($1399.00 @ PCCaseGear)
Case: Phanteks - ECLIPSE P400S TEMPERED GLASS ATX Mid Tower Case ($129.00 @ PCCaseGear)
Power Supply: EVGA - SuperNOVA G3 750W 80+ Gold Certified Fully-Modular ATX Power Supply ($179.00 @ Shopping Express)
Operating System: Microsoft - Windows 10 Home OEM 64-bit ($124.00 @ Shopping Express)
Keyboard: Logitech - G810 Orion Spectrum RGB Wired Gaming Keyboard ($138.00 @ Shopping Express)
Mouse: Logitech - G502 Proteus Spectrum Wired Optical Mouse ($79.00 @ IJK)
Headphones: Logitech - G933 Artemis Spectrum 7.1 Channel Headset ($195.00 @ Shopping Express)
Total: $3842.00
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2018-03-18 15:02 AEDT+1100
Includes OS, Headset, Mouse and Keyboard.
Also note that there is a new GPU release around the corner so you might want to wait for more options.
The 1080Ti is a powerful card, but 4k is very demanding. 60FPS should happen, but might not all the time.