Good luck! I started out with a Solsylva machine as well a many others here, and it's a great learning experience... Even had my machine posted on his site for a long while, before he redesigned the plans. a 1.5kW spindle and inverter is so cheap off eBay nowadays, and you won't be limited by just using 1/4" or 3/8" shank bits as you can get ER collets. For the steppers, I think the best deal is Leadshine DM542E which is very inexpensive (about $40 each or less) yet is feature packed. 48V would be a good PSU choice. Buy bits and endmills as you need them; don't buy kits with bits you'll never use. Check out the CAM section for software.