Intel Celeron G530 Dual Core Sandy Bridge Processor 2.4GHZ 57$Gigabyte H61M-S2P-B3 mATX LGA1155 65$Mushkin Enhanced Silverline Stiletto 4GB 2X2GB 25$Seagate Barracuda 7200.12 500GB 46$OCZ ModXStream Pro 500W 40$Antec Three Hundred Mini Tower Gaming Case 300 50$Powercolor Radeon HD 6770 for 85$total of 368, so what do you think, certainly not high end but its not ment to be
i doubt that you will find plans for free unless you have a friend that already bought the plans and has finished their planethe plans however are cheap enough to buy, around $150 or so as i recallshould you build a two seater or a single seater? that is a good question, and one that many home builders have pondered over the yearsif you plan on being the only person to fly in the plane, and you dont have any plans to sell the plane, then build the single seaterif on the other hand you may want to take someone along with you from time to time, or plan to sell the aircraft, then build the two seateryou will spend a bit more in materials, but not muchnow can you build the plane using aluminum tubingyes you can, but you will need to do your own stress analysis to make sure you get the airframe rightthe plans were designed and tested using woodif you are looking to reduce the weight of the aircraft, i doubt you will see enough weight reduction to make a difference in the endwood is quite ridged and just about as tough and light as aluminum ismy advice is stick to the plans as far as materials go, and you wont go wrongafter you have some experience under your belt, then you can redesign the aircraft if you like.
Seem's OK for a budget buildMaybe you could bump it up a bit more to get a i3 2100Otherwise, it seems OKYou can get a cheaper power supplyYou could run a 6770 and i5 / i3 on a 400W with no problemsSeems balanced very well, 8/10 for components chosen.
If I ever build an airplane I would want two seatsFlying is so much more fun when you can share it with someone else.