building is half the fun! It's not really a skill level thing, but more of a patience thing.
plus, (no offense) if you're not willing to take the time to learn how it works and how to build them, if it breaks or needs maitenance, you'll be clueless. You need to learn g-code, have a cam and cad package, and know cad to use a cnc router. also, have you looked at www.kleinbauer.com yet? he has many good plans too.
materials would probably be about $200 + $300 for the steppers, controller board, and power supply if you went the www.hobbycnc.com route. Softwae alone is very expensive. you could use a9cad which is free but doesn't seen very popular.
a cam program is anywhere from $60 upwards. Turbocnc (dos) is $60 Mach2 (more popular and runs in windows) is $150. assuming you leave the cad program out, you'll be spending over $1000.
what are you planning on cutting with it?
hope my post offers you some insights.