Re: power supply
I think that this is a not difficult to be make, all is depend from your skills.
If you want good and compact power supply you must use switching mode PS.
See link below, this is a very good SMPS controllers, in the site you an find soft for calculation, but you must know that PSPU quality is directly connected to the transformer quality.
And ... i not sure that home made power supply will be cheaper from original, but if you want to try this IS is good solution.
h**p://powerint.com/