Who has built their own house? Some advice?

Im looking in to every avenue of getting a house. In my area I can buy huge lots of land for 5k, zoned for residential usage.

Anyone build a house? What did materials cost you? What did the city and all their crap cost you? How long did it take? What took you the longest? What costs the most? What did you build?

Im interested in doing this with some friends, but want to see if anyone has some input first.

I haven't built a house but i have built some sheds. Of course everything depends on the sq ft of the house. bigger house=more lumber=bigger footing needed etc. a majority of the wood costs would go to 2x4's and plywood. and depending on the length of the 2x4's depends on the cost. 8ft 2x4s is about $2 ea i think, depending on where you are.
also gatta think about the tools you need to build it with. saws, drills, levels, framing squares....
you might have hire someone with a backhoe to dig the footing. this might depend on where you live, how far you have to dig down. and imo the hardest part of the job would be the roof. getting the rafters and joists just right, then the shingle work and trying to get those straight as possible.
but the best investment you could probably make would be a good book in carpentry. and you might be able to find various city codes online. im guessing 20-30,000k to build but thats just a pure guess. too many variables really. google is a nice tool too. but good luck. i hope to build a house of my own one day also..

something else you might want to try is download google sketch up and build the house frame that way first. it'll give you a visual idea of what the expect. thats what im currently doing.