how hard is building a bike?
any tips or good cheap toolkits for the job?
anything i need to go to a lbs for?
i am thinking of builing up 2 cross bikes for 07

Not very
Best tip is don't buy cheap
Yes
Cool

Now the longer answer. Unless you really want to spend heaps setting yourself up then the lbs will be necessary for fitting the headset cups, crown race and facing the BB shell. I also run taps through all the threads, but not that isn't 100% necessary, nor expensive for home use.

All good tools cost a fair bit, but if you want to do lots of work on your bikes (is there any other way in cross?) then the money spent will be worth it more than a damaged tool and part.

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Success is how far you you bounce back up after being knocked down

I like building things & knowing how to build things. I have experience with cars, bicycles(now ) home improvement, guitars, etc, etc. My suggestion would be to find yourself a good mechanic the first time who is willing to build it with you. Buy the parts from their shop with the condition that you get to be there for the build so that you can learn how it is done correctly. A good mechanic knows through hard luck & experience how to do everything correctly the first time. That is always invaluable with any project. I've screwed enough things up to know